Continuity mistake: In season 2, episode 5, Jin and Mr. Eko are searching for Michael. Jin gets attacked by a boar and rolls down a hill to find the corpse of Goodwin. In this scene they are in the middle of the jungle. Two epiosdes later ("The Other 48 Days"), when Ana-Lucia confronts Goodwin they are on top of a mountain without trees surrounding them. This is confirmed in Juliets flashbacks in later seasons when Ben takes her to see Goodwins body.Hovis63
Factual error: This is across the whole show, but made perfectly clear in the episode "The Whole Truth" (Season 2). Korean women do not change their last names upon marriage. A woman in Korea cannot be identified by name as someone's wife. And they would never be addressed that way. But Sun's fertility doctor addresses her as "Mrs. Kwon". Korean women can adopt their husband's family name if they move to a country where that is commonplace, but Sun was still in Korea at this point, and even after they crashed on the island, she had only just left the country.
Continuity mistake: Jin is handcuffed in season 1, "House of the Rising Sun" and the cuff remains on his left wrist until season 2, "What Kate Did" when Locke removes it. The handcuffs have a distinctive shape - a single strand connected via pivot to a double strand with the lock area. When Jin is initially cuffed to the plane wreckage, the single strand faces out at his wrist, but in following shots, in this and all the subsequent episodes, the handcuff actually switches sides repeatedly, going round his wrist the opposite way.Super Grover
Continuity mistake: On the airplane, the same passengers are seen in numerous shots with different main characters, and purportedly Kate and Marshal Mars (row 25) are in the same cabin on the opposite side of Jack, Rose and Locke (rows 23 & 24), yet are not seen in shots where they should be seen - though in shots of Jack and Rose, during the turbulance, the same woman and man (behind Locke) fly up as in the Kate and marshal shot. Some examples: When Kate and the marshal are shown during the turbulance, note the red-haired man with the black shirt beside the marshal and other men behind, and in one shot of Kate and the marshal, a woman and man both fly up to the ceiling of the cabin. In some shots of the turbulance, when the red-haired man is seen, the marshal and Kate are gone, replaced by other passengers. Just before the tail section breaks off, men behind the red-haired guy have either changed seats or disappeared, and so forth. Row numbers seen on the luggage compartments overhead are inconsistent with passenger seating. Such as when the tail section breaks off, the man is pulled out from row 26, yet the number above reads 13, or when Claire boards the numbers overhead are 20, 21, 22, yet Jack is in row 23, which is the second row behind the wall. The interiors of the Oceanic airplane also significantly differ in various shots. One example - the seats on the airplane have blue square velcro coverings on the passengers' seat headrests, and long, wide magazine racks on the divider wall behind Locke, but when they carry Locke onto the airplane, they don't exist.Super Grover
Continuity mistake: When Kate finds the pilot's wingpin in the mud, the pilot's reflection is seen in the water as he lies on the branches above Kate. When Jack approaches they all look up and in the overhead shot the pilot's position differs and he lies on different parts of the branches, note their shape.
Other mistake: The Monster appearing in the pilot and causing the turbine to explode is a mistake (not trivia). This is actually an artefact of poor CGI effects that was left in the show in error. It was confirmed by the producers. You can see it best here: http://www.lostpedia.com/wiki/Image:Turbine_Explosion.gif.
Continuity mistake: 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.Super Grover
Continuity mistake: When Jack drops to his knees, after removing the undershirt, one white shirt lies stretched out horizontally on the ground directly in front of him, with both knees centered in front of it; the other shirt is off to his right (viewer's left), with the undershirt he drops. Three shots later, still on his knees, all three shirts lie rumpled to his right; eleven shots later, the single white shirt once again lies horizontally directly in front of him, in the very same position as the earlier shot.Super Grover
Continuity mistake: 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 (grey stripe seats and roomier) - where Boone and Shannon sit. 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.Super Grover
Continuity mistake: In the very beginning of the pilot episode, Jack runs out of the jungle. He looks around and hears distant screams. While he is looking around, you can see through the bushes that there is nothing but beach on the other side. But when he turns around, the entire beach just on the other side of that bush is filled with wreckage. The wreckage would have been visible from the other side of the bush had it been there.