Deliberate mistake: In the scene with all the coffins and new Skull "recruits", Lucas knocks on the unopened coffin and Caleb pops up. The next shot is a wider shot that shows everyone standing around Caleb's coffin, but the guy in the coffin is not the actor playing Caleb, but a stand-in.
Deliberate mistake: When the board member is shot up in the beginning by ED-209, in one or two shots you can see the bullet impacts happen about 1/2 a second after the shot starts (Criterion DVD version). (00:11:55)
Deliberate mistake: During the fight at the Unity Day Festival, at one point Goblin is confronted by some cops and beats them up. Watch closely... you can tell that the first and second shots are just different takes of the same stunt from a different camera angle. Goblin's movies are exactly the same (except slightly faster in the second shot), and you can also tell it's the exact same two cops he's hitting. They tried to artificially lengthen the scene by showing two slightly different takes of the stunt.
Deliberate mistake: When Mr. Roboto is offering Austin a mushroom, the subtitles lead Austin to think Mr. Roboto is asking him to eat some shit, until Foxy reveals more of the subtitles to say "Please eat some shitake mushrooms." The correct spelling for this kind of mushroom is "shiitake." They had to cheat on the spelling in order to make the joke work.
Deliberate mistake: After Bert is shot in his car, Bobby pulls up beside him and just after Bobby shouts, "Pop, pull over!" the first time, the next tight close-up of Bobby's face is a flipped shot. Note his earring and the scar on his upper lip have switched sides. (01:17:00)
Deliberate mistake: At the end during the car chase, the blue car goes under the lorry trailer. All tailors are fitted with safety side bars to stop this happening, they have been deliberately removed for the action scene.
Deliberate mistake: When they fight in the hangar and Troy is thrown back by the jet engine, his face and other parts of his body should have been burnt quite heavily. Such a jet engine has temperatures higher than 450°C about 5 meters away, and Troy is even closer than that.
Deliberate mistake: When Sean James is reading 'The A-Z of Hip Hop' he reads 'whack' and 'dis' and their meanings out loud without turning the pages. The letters 'W' and 'D' are nowhere near each other in the English alphabet.
Deliberate mistake: When John crashes the car against the elevator room, the cables he and the woman hold on to are clean, when they should be greasy - thus allowing for them to hold safely.
Deliberate mistake: As Roper drives the Dodge into the shipyard watch the underside - no sign of McCall, even though he's visible under the body when he comes out of hiding.
Deliberate mistake: When Robocain tries to use his chaingun on Robocop and it isn't armed, he snatches the remote unit from the OCP psychiatrist. If you look carefully, the remote unit changes from real to animated as soon as he grabs it.
Deliberate mistake: The dummies are obvious when the jail bus is flipping over onto the railroad tracks.
Deliberate mistake: When Riggs is chasing the guy on foot, you can clearly see it is a stunt double, who is also very apparent in other shots throughout the film.
Deliberate mistake: A stunt double for 47 got hurt on camera and yelled, very obviously. Right after the sword fight on the train the last man 47 is fighting continues the fight hand to hand under the tracks. Timothy Olyphants stunt double throws a punch and he grips his hand, yells and his face comes into screen for a moment. Next shot, Timothy Olyphant throwing his own punches.
Deliberate mistake: Denzel Washington never wears a vest (at least during the previews). All deputies are mandated to wear at least a level II vest (most will buy a higher protection vest) whenever performing Sheriff duties. Plus his duty shirt is just plain sloppy looking, way too big for him.
Deliberate mistake: At the beginning of the movie, Ashtray gets his hair lined up saying, "Kick Me". However, in the rest of the movie, like the scene where he hugs his grandma, it shows the back of his head and there is no words.
Deliberate mistake: Nearly every night scene inside the house is lit by very bright lights shining in the windows from outside. Yet every time anyone is outside the house, it's still just as dark. There is no light source from which these lights could possibly originate.
Deliberate mistake: Hollis Mulwray walks out to the ocean and it's obviously sunset. In the next shot we see Jake's face up close and it's obviously mid-afternoon. (00:11:05)
Deliberate mistake: When Reese is looking at Starsky and Hutch's police profiles, his brunette girlfriend says, "Ooh, he's cute, the blonde", referring to Hutch. From the way she says it, it sounds like she's referring to the picture, however you cannot see Hutch's hair in the picture. She had not previously met Starsky and Hutch, either, as it was Resse's blonde wife that was in the room at the time. (00:28:40)
Deliberate mistake: Jimmy catches a fly in the air and puts it in his mouth. He then spits it out with great power. You then hear a "Bzzzzz." assuredly made by the fly. How can a fly flap its wings when spit out in that velocity? (00:48:30)