Avid fans of LOST have located many, many mistakes on LOST regarding props, dates, discrepancies in the hatch, changes that occur in the hatch mural, jewelry that appears and disappears or moves from one part of the body to the another, flipped shots that result in mirror images, sudden changes in clothing, etc.

My goal is to try to list all the 'mistakes' in one place. To date, these are the most comprehensive lists of the LOST 'mistakes' available anywhere.

What you will not find in this list are lots of the instances where a piece of production equipment is inadvertently seen, or a shot that has obviously been flipped such as those described by Richard Sickler on the S2 DVD. An example of one of these, is when the shots are flipped to give the impression of a car with a right-sided steering wheel vs. a left-sided steering wheel. These types of images are only included here if one or more item changes and everything else in the shot stays the same (i.e.: Eko's earring changes ears while everything else in the scene stays the same S2E10).

TPTB have stated that many of these 'mistakes' are simply errors that occurred in editing and that LOST fans shouldn't pay much attention to them. According to JAVI over on The Fuselage, "Sometimes a cigar is just a cigar".

However, TPTB have also stated that some of the so-called mistakes are actually intentional and that they are important to LOST.

That leaves the viewer wondering which of the 'mistakes' are important and which of the 'mistakes' probably do not mean anything. There are many threads on a variety of boards that discuss these mistakes and their possible importance.

I have also assembled a list of Mistakes That Are Important. This list includes items that are just too important to the story to be as carelessly handled as they would appear to be.

I am referring to the 'mistakes' that occur with the single most important prop that each of the LOSTies is associated with. I simply can not believe that the most important props on the show would be dealt with so carelessly and I do not believe that there is a snowball's chance in hell that the Props Department is solely responsible for these. The person responsible for these types of errors would, at best, be damn sure they didn't happen again. And, at worst, they would be fired.

I believe these are not casual 'mistakes', but 'mistakes' that the audience is meant to find and that they mean something. Perhaps the prop changes depending on the role that the character is in at that particular moment.

Ben's Picture
The picture of Ben's mother has changed from a younger woman with hair down over her left shoulder, to the version of the picture seen in S4E7 where she is an older woman with no hair over her left shoulder. The older version of the picture is also seen in S4E9.

Charlie
After watching Charlie's guitar for three seasons, I have still been unable to find any differences with either it, or the guitar case. However, in S3E21 there were many differences seen with the props associated with Charlie.

The most notable of these can be found in Charlie's list of his "Greatest Hits". We see Charlie's list on five different occasions as he starts with #5 and then adds #4, #3, #2 and finally #1 to the list. But if you compare the list as it is seen each time he adds something to it, there are big differences in the list. Look at the list when he is adding #4, the words "First Time" are separated, they were connected in #5. When he adds #3 to the list, the position of the word "Butlin's" has changed position in relation to the word "radio"; and the words "First Time" are now connected again. There are also big differences in the presence of absence of the periods after each entry on his list. And there are distinct differences between when he adds #2 and #1. The placement of the words "Hero" and "Covent" are different in relation to each other.

In S3E21, Charlie is seen placing the Drive Shaft ring on his middle finger when Liam gives it to him and Charlie announces "It fits". Yet, when Charlie is seen wearing the ring on the street corner near Covent Garden he is wearing the ring on his fore finger.

The length of Charlie's necklace also changes constantly throughout S3E21. It some scenes it hangs down over the neckline of his t-shirt and in other scenes, it is much shorter.

Claire & Her Diary
In S1E2, the diary that Claire is shown writing in appears to be a very dark blue, even black in color with a stiff cover.
In S1E14, the diary that Sawyer gives to Charlie is a brighter blue and has a soft cover. Also, see the screen cap from the scene where Charlie tries to avoid reading the diary, it is soft covered and the brighter blue color

There are also some curious differences in the handwriting shown in Claire's diary in S1E14. Look carefully at the a's. It appears as if two different people have written in her diary. It's also interesting to note that the top two screen caps from the diary seem to be typical of the dialogue we expect from Claire, all sweetness and 'light' and that the bottom screen cap contains words like HATE and suck. It could be an indication of Claire being in a 'good' role when she writes the top parts and a 'bad' role when she writes the part in the bottom screen cap.

Daniel's Map Back to the Boat
In S4E5, two different versions are shown of the map that Daniel drew for Frank to get back to the boat. The boat is drawn differently, the writing is different and they are positioned differently on the instrument panel.

Desmond's Picture of Penny & Her Letter
There are two different versions of Penny's Letter, Letter 1 and Letter 2 and there are also two versions of the picture of Desmond & Penny. Penny is wearing a black shirt the first time we see her picture in S2E3. In S2E24, there is a different Penny and she is wearing a white shirt. Different actress, yes, but why change what she is wearing? And why go to so much trouble to have her clothes completely reversed from a black blouse with a white t-shirt underneath to a white blouse with a black t-shirt underneath?

Eko & the Drug Plane
Eko is responsible for bringing the Beechcraft with the heroin to the island. When the plane is on the tarmac in Nigeria it had large numbers on it's side S2E10, but when Eko makes Charlie take him to the plane in S1E10, the numbers are different and smaller.

Hurley & The Lottery Ticket
In S1E18, the numbers are seen near the top of the lottery ticket.
In S2E4, the numbers are shown near the top of the lottery ticket at the beginning of the episode and then every other time it is shown in this episode the numbers are closer to the bottom of the ticket.

Jack & His Father's Body/Coffin
In S1E4, when Jack sees the empty coffin, the things lying on it change between shots, and the lining changes from one shot to the next. The amount of destruction Jack has done to the coffin also changes between shots.
The only other item that Jack has with him after the crash is a Russian vodka bottle.

Jin & Mr. Paik's Watch
The most interesting mistakes about Jin, Michael and Mr. Paik's watch occur during the fight scene in S1E6 where the watch appears and disappears from Michael's wrist. But the watch that Jin is wearing in these scenes appears and disappears as well.

Kate & The Toy Plane
In S2E9, there are no numbers on the wing of the plane
In S1E12, the numbers 5025 are on the top of the right wing of the plane, also seen here when Kate holds up the plane

Kate's Trial
Most of Kate's crimes are state crimes and she’d be tried in the state of her crimes. The charge of assault on a Federal officer would probably be a federal crime and be tried in a different court. But none took place in LA and there’s no reason she’d be tried there.

Locke & His Compass
In S1E13 and in all other episodes, Locke's compass is silver.
In S1E13, the compass is gold when he hands it to Sayid.

Locke's Date of Birth
Locke's license and the firearms permit show two different birth dates. Also, in California, driver’s licenses use your birth date as an expiration date. In addition, the zip codes do not match. The zip code on the Firearms permit is 94099 (which is South San Francisco, not a San Francisco Zip Code (it is another city), and on his license is 94131 (which is San Francisco). In addition. Emily Locke's driver's license said her date of birth was 1940. So was Emily Locke 6 years old when she gave birth to Locke? And why does her driver's license say that the license expires on 3-20-94 when it also says that the driver's license "expires on birthday". In S3E13, we were given an entirely different date of birth for Locke on the paperwork that Tamara the Social Worker is filling out. These papers appear to say that his Date of Birth is 5/20/56.

Michael & His Letters to Walt
Look at the two pictures, one is of Michael when he is sketching the card, the second is the finished card. Note the differences in the window on the equipment, the size and location of the cake, the position of the feet and bandages and lots more.

Rose & Bernard's Wedding Ring
In S1E1, Bernard’s wedding ring is not on the chain around Rose’s neck when she is speaking to Jack as he gets up from his seat just before the plane crash.
In S1E1, the ring is on her neck when she is seen on the beach immediately after the crash.

Sawyer & His Letter to the Real Sawyer
In S1E16, Sawyer is seen reading the letter he wrote to the Real Sawyer.
In S3E19 Sawyer gives Anthony Cooper the letter to read
The letter shown in S1E16 is much shorter than the letter that Anthony Cooper reads

Sayid & His Pictures of Nadia
There are differences in what is written on the back of Nadia's picture from one scene in S1E9 to another, the writing is actually reversed. The wording on the back of the picture has also been deliberately changed from the common Arabic phrase which means that they would meet in heaven vs. the wording which now says that they will meet in "another life"

The Plane
In S1E1 the wings of the plane are still attached to the fuselage
In S3E1, the wings of the plane break off while the plane is still in the air

Walt & Vincent
I'll be going back to get screen shots of Vincent and his leash, it has been blue in some episodes and red in other episodes. In S3E21 Hurley is seen with Vincent on a leash that is made from what appears to be chain.

Dating & timing have been a issue on LOST since the very first episode. Beginning with the many pieces of information that have caused the crash date to be debated (the 2004 vs. 2009 controversy).

Some dating mistakes have been explained by TPTB.

TPTB have stated that the date on Jin's resume was a production error. That the postmarks on Michael's letters to Walt that were featured on the Oceanic-Air.com website do not match the timing when Susan and Walt were living in specific countries and were an error. And that the date from Jack's luggage tag was just wrong.

I firmly believe that the writers are deliberately including conflicting dates and timelines in numerous episodes. TPTB stated in the May 26, 2006 podcast that the date of the crash was September 22, 2004, I remain convinced that the date of the crash and the timing conflicts are key to LOST.

During Comic Con in July 2006, TPTB stated that "the survivors may not actually be on the island as long as they think they have been." So, it looks like we will be getting more dating and timing conflicts in Season 3. I still find it curious that only two years were ever indicated for the date of crash. Either 2004 or 2009. If these are truly random errors then why do they always only point to one of these two years?

There are some other dating issues have not been explained, including:

• In Season 1 Boone dies on day 36. Yet, Bernard speaks to him on the radio on Day 41 in S2E7.

• In S2E7 Cindy says that the plane was flying for 6 hours before the pilot turned around and flew for 2 hours in the wrong direction. This equals a total of 8 hours of flight time. Yet, Ana Lucia says that they were flying for 2 hours and she didn't see Nathan on the flight.

• In S2E11, the x-ray is dated 11/16/2005

• In S3E1 Christian Shephard is shown driving a 2007 Mercedes up to the hotel (confirmed by Mercedes-Benz of San Diego)

• Locke's license and the firearms permit show two different birth dates. Also, in California, driver’s licenses use your birth date as an expiration date. In addition, the zip codes do not match. The zip code on the Firearms permit is 94099 (which is South San Francisco, not a San Francisco Zip Code (it is another city), and on his license is 94131 (which is San Francisco). In addition. Emily Locke's driver's license said her date of birth was 1940. So was Emily Locke 6 years old when she gave birth to Locke? And why does her driver's license say that the license expires on 3-20-94 when it also says that the driver's license "expires on birthday". In S3E13, we were given an entirely different date of birth for Locke on the paperwork that Tamara the Social Worker is filling out. These papers appear to say that his Date of Birth is 5/20/56.

• In S3E14 Locke is watching the episode of Expose that Nikki finished just before leaving Australia in 2004. However, Locke is not paralyzed and we were told that he spent four years in the wheelchair before he went to Australia.

• In S3E17, in Desmond's last flashback, he was in the monastery in 1995 before he met Penny; yet, in S3E8 it was 1996 and he'd been with her for two years.

• In S3E18 Juliet says that it is Saturday when she leaves the message for Ben, yet early in the episode she referred to the LOSTies having been there for 90 days. Day 90 would actually be a Monday. Day 88 would have been a Saturday.

• In S3E20, the books on the classroom shelf include "The Coalwood Way" by Homer Hickam. It was published in 2000. This scene is supposed to take place some time in the 1970's

• S4E5, the Black Rock leaves England in 1845, but dynamite, which was invented in1866, was found on the Black Rock

• S4E6 Juliet says it's been three weeks since they lost Ethan, but in fact, Ethan did not die until day 29

• S4E7, in Jin's flashback, he pulls South Korean won bills that recently came into circulation out of his wallet. The 10,000 won bills he pulls out were released on January 22, 2007

• S4E7, the first scene of Jin in the toy store shows items on the back shelf from the shows Ben 10 and Power Rangers: Operation Overdrive. These shows did not begin airing until 2007. Another shelf carries Nintendo DS and PSP consoles, which were not available until late 2004

All 'Mistakes'

• After the plane crashes, the same people keep running in and out of the background behind the main characters.
• When Kate finds the pilot's wings (pin) in the mud, the pilot's reflection is seen in the water as he lies on the branches. Later when Jack looks up, the pilot's position has changed and he is lying on different branches.
• Watch Jack's t-shirt when he drops to his knees and takes it off. The positions of his shirt and t-shirt change.
• When Charlie leaves his seat on the airplane, as he is followed by the stewards, he walks through economy (blue stripe seats), then walks through business class. But, in Charlie's next close-up, when the plane shakes, he leans on the blue seat in front of him, which he already passed and is farther back in the plane's cabin.
• When Charlie, Kate and Jack are in the nose wreckage, to find the transceiver, there is a shot in first class, facing the cockpit, showing the glass wall with the decorative circular design. When Charlie is aboard the flight, running from the stewards, he stands beside that glass wall, and the circular pattern is reversed. Neither shot is flipped.
• Jack, Hurley and Claire are running from the wing that is falling down, as Jack says "stay with her", Hurley has a big piece of his hair across his forehead that appears and disappears between shots.
• When Kate, Jack and Charlie are talking to the pilot, the blood on the pilot's face changes position.
• The ring is on Rose's chain in S1S1 when she is seen kissing the ring (DVD 13 minutes). Rose does not have Bernard's ring on the chain around her neck during her conversation with Jack just prior to the crash S1E1 (DVD 22 minutes). This scene is immediately prior to the crash and Bernard is already in the bathroom. Rose should have had his ring on the chain by then.

• When Jin offers Claire some of the sea urchin, the position of the book changes in her hands.
• Watch as Sawyer and Sayid are fighting and Jack tries to pull Sawyer away. Sayid is first holding onto Sawyer's shirt, next he is holding onto his pants.
• There is also a repeated shot during the fight scene when Jack is shown grabbing Sawyer's left arm twice.
• When Sayid is taking the transceiver apart, the part in his hand seems to move back and forth from his right to his left hand, to the table.
• As Jack, Charlie and Kate are walking through the woods, Jack is holding the transceiver and Charlie asks if he hears anything. Jack answers "You keep asking if there's anything", while holding the transceiver with his right hand and his left hand is down. When it cuts he holds on to the transceiver with both hands.
• On the airplane, Kate lifts the glass of juice with her handcuffed hands, in this close-up the cuff round her right wrist has the single bar facing out. However, when the turbulence hits, in another close-up of her hands, the same cuff is on the opposite way, it now has the double bar facing out.
•During the flashback, Charlie goes to the bathroom at the front of the plane. Once the plane hits turbulence, Charlie gets out of the bathroom and is able to make it back about 10 rows before strapping himself into a grey seat, not the blue seats found in coach class. Boone and Shannon were seated in Business Class in grey seats, so Charlie is probably seated somewhere near them when the plane goes down. Sawyer says that Sayid was seated in business class near him in S1E2. Sawyer is seen sitting on a grey seat on the beach in S1E8. When Kate, Charlie and Jack visit the front section of the plane, this section contains at least 10 windows which would imply that the first 10 rows of seats are there. So how could Sayid, Sawyer, Charlie, Boone and Shannon wind up on the beach and not wind up with the front part of the plane?

• The endless line of telephone poles seen as Kate & Farmer Ray and the Marshall drive along the road repeatedly switch sides.
• The tailgate on the pickup truck is present, then it disappears, then it is back again. Also watch the cab window behind Kate and Farmer Ray, it switches from being closed to being open. When Kate grabs for the steering wheel in the side exterior shot, the stunt driver is visible and he is holding the steering wheel with his right hand. Farmer Ray has a prosthetic right hand and is previously seen holding onto the steering wheel with his left hand.
• Watch Farmer Ray's bruises, his suspenders and his wedding ring as Kate drags him away from the burning pickup, his bruises switch position, his suspenders are not clasped & then they are, and his wedding ring changes from his left hand to his right hand. Kate's bracelet also switches wrists. And Farmer Ray's hat moves from being dropped beside the door to being about eight feet away.
• Sun's face changes from being only slightly dirty to completely dirty as she is bringing the luggage to Jin and he tells her to "Go wash up".
• While Michael searches for Vincent and meets up with Sun, his shirt changes back and forth from being wet from the rain to, dry.
• The position of the firewood changes when Kate is building the fire, to it's configuration when Sawyer joins her.
• When they make camp for the night, on their way back from hearing the French woman's transmission, they sit around the fire talking. Sawyer has a cut over his right eye, but in every other close-up of Sawyer the cut is over his left eye.
• As Kate leans over the marshal, he wakes up and chokes her and as Jack subdues him the marshal's large head bandage falls off. When Jack squeezes water into the marshal's mouth, the bandages are wrapped perfectly round his head, yet when Kate stands up the bandages are off again.
• When Jack removes the paper with Kate's mug shot from the marshal's jacket pocket, in the close-up of the paper there is no writing at the top center of the paper, only at the sides. However, in the previous shot the center writing is visible from behind, and is also perfectly seen when Hurley finds the paper.
• Watch Walt's sleeping position as Locke tells Michael "I thought you should be the one to bring his dog back to him". Walt is facing away from Michael, then faces towards Michael and then faces back away again.
• Kate eats bacon when Farmer Ray feeds her, but in S1E4 she tells Jack she is a vegetarian.

• There is a safety wire visibly attached to Jack's waist as he is hanging off the cliff and the number of leaves on the vine changes from its appearance in wide-shots to its appearance in close-up shots.
• When Charlie and Hurley are questioning Jack in the tent, a man and a woman walk behind Jack in the same direction twice
• Watch the suitcase filled with water bottles, the number of bottles appears to keep changing.
• Boone's sitting position changes during the conversation when Sawyer asks him "So how does it feel?"
• When Jack sees the coffin, the things lying on it change between shots and the lining changes from one shot to the next. The amount of destruction Jack has done to the coffin also changes between shots.
• In S1E1, Kate sews up the deep cut on Jack's back. When he dives into the water (twice) to attempt to rescue Joanna, it is only 6 days later and the cut is gone. How could Jack have healed so quickly?

• When Sawyer removes the handcuffs from his pocket, the chain is shorter than it is when we see Jin chained to the wreckage.
• As Jack and Kate head back to the beach, the bag on Kate's shoulder keeps switching positions.
• Kate takes her shirt off in the cave when she is fighting off the bees, but when Charlie walks in, he says she left it outside the cave.
• There is a large blood stain on Jin's right elbow when he is washing his hands. In the next shot the stain has disappeared.
• When Jin attacks Michael, the wreckage on the beach beside the wheels is seen behind Sun as she shouts at Jin. When Jin is handcuffed, the wreckage on the beach differs, there is noticeably much more in that area.
• Sun's left earlobe has a cleft, but while Jin is still cuffed to the wreckage, Sun watches Michael head off through the trees (to cut firewood) and in this close-up it is Sun's right earlobe with the cleft.
• The way Sun is holding the puppy switches between shots.
• At the party when Jin and Sun are standing together, Sun place her arms on Jin's shoulders. Her arm's position on the shoulders differ between the shots.
• At the end of the episode, while Jack is filling his water bottle, his tattoo is on his right arm, not on his left.
• The tattoo also switches arms when Jack is in the second fight with Ethan.
• As Michael is surprised to learn that Sun can speak English, the arm he has extended changes.
• In S1E1, Kate sews up the deep cut on Jack's back. When he dives into the water (twice) to attempt to rescue Joanna, it is only 6 days later and the cut is gone. The cut is also gone in S1E6 when he takes off his shirt in the cave during the bee attack. How could Jack have healed so quickly?
• The gold watch disappears from Michael's wrist when Jin is fighting with him in the water. Also, in the first six episodes, Michael is usually shown wearing a watch. In S1E1, S1E2, S1E3 and S1E4, Michael is wearing a watch on his left wrist that has a brown leather strap. In S1E5 Michael doesn't wear either watch. In S1E6, Michael wears the gold watch on his right wrist. Also, keep an eye on Jin's wrist. his watch appears and disappears as well.

• When Charlie and Liam are speaking outside the church, Charlie's scarf changes position.
• When Charlie visits Liam, the items on the table near the lemonade pitcher switch positions.
• We see the suitcase fall from the net when they are trapping the boar, a few scenes later, the suitcase is still falling.
• Watch Charlie's guitar case, we see it on the ground behind Charlie when he is playing and Hurley then brings the case to him.
• There is a brief shot of the tape on Charlie's fingers being on his right hand instead of his left hand as he is looking through Jack's drugs.

• The foot that Sayid gets caught in the trap changes from left to right, and the branch that he is stabbed with changes.
• After they discuss Nadia, the position that Danielle is holding the gun in that she is pointing at Sayid changes.
• When Sayid holds the music box open for Danielle to see, in the shots facing Sayid he holds it facing out towards Danielle, but in the shots facing Danielle, the box faces to the side.
• The cable Sayid finds in S1E9 is grey, the cable Hurley finds in S1E18 is black. They are obviously different cables.
• Emily Locke clearly has blue eyes, but her driver's license says that they are brown

• The bandage on Sawyer's arm changes from the type seen before he enters the water, to the one seen in the underwater shots.
• The position of the corpses and their clothing changes (look at the the left foot) from one shot to the next.
• Kate's bracelet appears, disappears and changes wrists when they are at the waterfall.
• The Halliburton has different handles and clasps from one shot to the next throughout this episode.
• When Jason the bank robber kisses Kate in the office, the position of his hands change.
• As Kate is getting whacked in the face by Jason, she is struck on the left cheek. When she exits from the office to the bank lobby, her right cheek is hurt.
• The design of the wings and the engines of the toy plane are very different from those seen in other episodes.
• Shannon's shawl is lying to the left of her just before Sayid approaches. When he begins speaking with her, the shawl is under her. Also watch the sandals change position.
• There are two different wallets used in the scene where Jack and Kate dig up the Marshall.
• When Boone accuses Shannon of not helping to move the camp away from the rising tide, he is wearing a t-shirt with a Chinese character on it that stands for 'good' and 'evil'. Moments later, his t-shirt has changed. I am not sure yet of the significance of the Chinese characters, but I am convinced that they are somehow important
• The position of the blinds behind the bank Manager (Mark Hutton) changes. First they are up and then down. Also, the position of the phone on his desk changes. And the light with the big globes behind Kate is not lit and then it is on.

• Locke throws the knife and it lands at a 45 degree angle, when Boone reaches for it, the knife is at a 90 degree angle.
• Locke's bag changes from being on his left shoulder to being across his chest. So does Boone's.
• Sun's watch appears and disappears.
• When Boone is tied up, his right hand is tied to his chest and his left hand is tied behind his back. This reverses when Boone reaches for the knife with his right hand.
• In this episode and in all previous episodes, when Locke is shown wearing the compass on his vest, it is silver colored. When he takes the compass off his vest and hands it over to Sayid it is gold colored. Sayid later discovers that the compass is defective. Is this showing that Locke is not cooperating because he actually hands over a compass that he does not generally use or rely on?
• When Sayid is trying to make a compass, the objects on top of the map change positions. Watch the knife and the plastic container.

• The body on the stretcher appears and disappears from the shot and the back door of the vehicle is opened and closed in different shots.
• Sayid places a glass mug on the table, when the bug is dropped into it, it is a different mug.
• Sayid's name tag flips.
• Essam's shirt changes positions over his shoulder in the garage scene.
• The rips and the hole in Sayid's black tank top change throughout the episode.
• The octagonal box appears in Essam's house S1E21, in Wayne Jensen's house in S2E9 and in the Swan hatch
• The blanket around Aaron changes positions throughout the episode.
• At the Nigerian plane, the tool chest on the plane is closed, yet it's open in the next shot.
• Sayid is told that Nadia is alive in S1E21, but in S1E9 he told Danielle she was dead. How can Nadia be dead in an earlier episode and alive in this episode? Perhaps we will find out that Sayid is told that Nadia is dead after all. This would have to occur sometime between the initial meeting with Sayid, Alyssa Cole and Robbie Hewitt and when Sayid gets on the plane the day after Essam commits suicide.