
Deliberate mistake: The Messerschmitts have painted yellow fronts, this wasn't done by the Germans until after Dunkirk. Christopher Nolan has admitted doing this deliberately so the audience could tell the difference between the Spitfire and the Messerschmitt during the combat scenes.

Deliberate mistake: Leaven spends too much time thinking about if 645 and 372 are prime numbers to be believable. But she knows the factors of 649 and the result of 26 to the power of 3 almost immediately. Plus anyone with any maths knowledge whatsoever would know that any even number (or one divisible by 5) can't be prime, so 645 and 372 could be dismissed without even thinking about it.

Deliberate mistake: In the fight scene with the chariots Maximus takes one of the horses from a chariot and jumps on it. The horse already has a saddle complete with stirrups despite the fact it was pulling a chariot and not carrying a rider. (01:23:30)

Deliberate mistake: When Elliott and ET are on the bike heading to the forest on Halloween night, ET is covered with the white sheet, but in the closeup of ET's face right before the bike flies he's covered with the white blanket (note the material), which is from the scene later in the movie.
Super Grover

Deliberate mistake: At graduation, after Troy is handed the diploma, in the overhead shot the graduates on the left and right stand-up from their seats, then turn and walk towards each other. All their seats simply disappear between shots. Obviously done deliberately for the dance sequence, but a mistake nonetheless.
Super Grover

Deliberate mistake: In the scene at the start of the movie with the "authentic" piece of film, you can see a girl with a hat waving to the people at the ground. When the ship is leaving port in the film, she and others are in the same positions, only in reverse, because the first "authentic" shot is the same shot, only mirrored. (00:00:40 - 00:25:30)

Deliberate mistake: Both in the first scene and last scene of the movie, we see Yolanda and Ringo starting the robbery by jumping from their seat and start threatening the costumers. In the first scene, Yolanda says "And I'll execute every motherfucking last one of you." But in the last scene the line changes to "and I'll execute every one of you motherfuckers". (00:04:40 - 02:18:00)
Amitai AssidoSuggested correction: Tarantino has explained that this is not an error, rather, he did this on purpose. When we first examine the scene, we are seeing Ringo and Yolanda's conversation from their perspective. Obviously, because this is their conversation, what we hear first is probably what was actually said. However, at the end of the film, what is said is different because we are no longer viewing the situation from Ringo and Yolanda's perspective, but rather everyone else in the diner, most specifically Jules.

Deliberate mistake: To make Jim Braddock look more heroic, Max Baer is portrayed as being very mean and hateful. In fact, the real Max Baer was an extremely pleasant man who was devastated when Frankie Campbell died after fighting him. Many boxing historians and sportswriters have complained about this inaccurate depiction of Baer.
wizard_of_gore

Deliberate mistake: When Eliza is about to be bathed, the mirror keeps turning around between shots to avoid reflecting the filming crew.
Sacha

Deliberate mistake: When Tarzan fights with the leopard, it scratches his chest. However after they fall into the pit and Tarzan comes out carrying the dead leopard, the scratches on his chest have amazingly healed. [It is a long-standing Disney tradition that no evidence of violence is shown on screen. Still a mistake, but there's why].

Deliberate mistake: In the towel-dance scene after Demi has put on her white panties and spins off the towel from her hair she starts to rip off her body towel. Then in the next frame the towel is again tucked in. Apparently they didn't want Demi topless when she leaned over to slip on her blue shorts.

Deliberate mistake: When Cristal and Zach's limo pulls up in front of the Club Cheetah, the Stardust is prominently displayed in the background at a close distance to the club. In reality, the Cheetah is a popular and well-known strip club in Las Vegas. People such as myself who have actually been there know that when looking at the Cheetah from the angle seen in the film, there would be no possible way the Stardust could be in the background (in actuality, the I-15 highway would be in the background, not the strip). (00:22:35)

Deliberate mistake: As Christine approaches the Phantom in his lair (just after he has abducted her), we see that she is wearing very dark black eye-shadow. Back in the dressing room after coming off stage, as she talks to Raoul, we saw her face in close up and she was not wearing any eye-shadow at all, even though the Phantom leads her through the mirror just after she has managed to slip on a robe over her undergarments and she has not yet changed to go out to supper (Raoul says she is to be ready in 2 minutes). Her hair becomes 'bigger' and wilder, too. The change in her appearance is a reference to her descending (voluntarily, I might add - he didn't drag her through that mirror) into the Phantom's dark existence and to her sexual awakening. (00:28:45 - 00:37:10)

Deliberate mistake: At no time can a player on the ice play without a helmet. It may be legal in professional hockey, but never in youth league games, world championships or not (This happens when the goalie comes out of the crease and takes his mask off to shoot his "knuckle-puck", as well as the penalty shot in the first movie.)

Deliberate mistake: In the torture scene, Mr Blonde turns the radio on and listens to "Stuck in the Middle with You" as he proceeds to torture the cop. Mr Orange shoots him before Mr Blonde turns the radio off, but somehow the radio is never heard again in the film.

Deliberate mistake: The same scene of William Bendix at bat swinging and missing is used repeatedly in the film.

Deliberate mistake: During the finale, the backround looks like a sunset and there is a big door in the back. Watch closely and all of a sudden from one camera angle to the next (it's right after the big puff of smoke), the background changes to an elaborate background of layers of hearts, the door is gone, and there are about 60 more extras onstage. During the DVD Baz explains that they filmed the scene with both backgrounds and it just so happened that the beginning was better with one and the end was better with the other, so they put the puff of smoke in there to distract the audience so that they wouldn't see the change.

Deliberate mistake: "Fury" director David Ayer acknowledges that he committed a deliberate error by having the German Tiger tank blast the last Sherman in the column, tank doctrine being that the lead vehicle in a column gets blasted, then the last to stall the column, leaving the vehicles in between the dead vehicles easy pickings. Ayer said if the doctrine was followed in the film, Brad Pitt's tank would have been destroyed first and thus the film would end, roll credits.
Scott215
Deliberate mistake: When Peter and Miraz are fighting, Peter stabs Miraz and then brings the sword back up for the killing stroke. There is no blood on the sword. This is deliberate on the part of Disney, so as not to show blood, but a mistake nonetheless.

Deliberate mistake: In one of the dogfight scenes a Japanese Zero crashes into a tower. It's a quick shot, but you can still see that what crashes is an American P-40 with Japanese markings.