Deliberate mistake: When Sam is watching the security footage of his predecessors being disintegrated in the chamber, the disintegration happens the instant the coffin door is shut. However when he goes in to test it himself there is a ~60 second wait as a congratulatory video plays before the disintegration occurs. (01:00:00)
Deliberate mistake: While Cohagen is on Mars, he calls Richter and chides him for trying to kill Quade. Richter is in a car on Earth, yet they're having a real-time conversation, which is impossible because of the distance. [While this is true, a movie with 4 to 21 minute pauses between lines would take rather a long time].
Deliberate mistake: The filmmakers wanted a scene where Andi is startled by Max as he spacewalks behind her at Daedalus. Given that the only way to communicate in spacesuits is through radio, and the two suits would presumably been on the same channel with the shuttle, Andi would have known Max was coming. Further, even if they were on different channels, why wouldn't anyone tell Andi that Max was coming?
Deliberate mistake: During the final battle, at one point Sean kicks Crane off a rope bridge. When this happens, if you look closely you can see the rope railing on the side of the bridge fall away right before Crane falls. It's supposed to look like Crane is falling through the ropes, but they drop just a split-second too early (he's not even touching them when they start to fall), so it was done on purpose and mistimed. (It was likely timed to drop away just a split-second before Crane fell so that the stunt-person wouldn't accidentally get tangled in the ropes as they fell).
Deliberate mistake: When King Shark grabs the guard from behind and eats him, he screams loudly, but nobody reacts to it, not even his buddy who just went left to fetch a drink. Later Cena and Elba kill 'silently' every other guard, but when they get to a group of three that Bloodsport yo-yos to death, it's pretty impossible that those three could have missed the carnage just a little off to the left. Then again, at the end a whole tower gets demolished without anyone noticing, so It'has to be deliberate. (00:33:05)
Deliberate mistake: For all exterior shots on the surface of Mars, the crew's "pressurized" space helmets have no face-plates (their faces are fully exposed to the hostile Martian environment). The transparent face-plates they intended to use reflected far too much studio set lighting, such that the glare would have obscured the actors' faces. On a $200,000 budget and a 10-day production deadline, they simply scrapped the face-plates and shot the scenes with wide-open helmets.
Deliberate mistake: At the speed trap, Tom points his radar gun at a turtle. From his perspective, he seems to be looking through some sort of scope with cross hairs and numbers on it at the turtle to line up the beam. However, when he then looks at the radar gun at the speed indicated as 1 MP/H, there is nothing on the gun where he could have been looking through such a scope. At best, the top of the run appears to have plastic iron sites. The scoped view would not have been from the device itself perspective since it would not need cross hairs or numbers on said cross hairs as that would be for a person looking through it to have reference points. This scope view of the turtle was most likely just added by the film makers to have a better visual representation of Tom aiming the radar gun at the turtle. (00:04:29)
Deliberate mistake: The scenes involving the 8mm projector and screen did not also contain legitimate light rays from the projector to screen or show any obstructions on the screen despite Joe or someone else between the projector and screen. What showed on the screen is what would be expected if using a videotape or DVD.