Movie elevators are always ready at that floor. But if the hero/heroine is being chased, elevator won't come.
If hero OR villian takes an elevator, villain OR hero can beat it by taking stairs, even if the trip is 20 floors.
Most elevator shafts and wires are clean and dust/grease free, and there's plenty of light so that the hero neither gets dirty nor needs a flashlight or some other equipment to see (Speed).
When one character is pursuing another and they reach the elevator just before it closes, they never stick their hand in the door so it will automatically open back up, nor do they press the call button to get the door to open.
ENVIRONMENT
Thunder and lightning always happen at the same time.
Storms start instantaneously: there's a crack of thunder and lightning, then heavy rain starts falling.
Heavy rain causes no loss of long-distance visibility.
Everything is blue at night-time.
Caves always have flat floors, and it's never fully dark.
There is always someone in the canal or the storm drain when the flood hits.
The moon is always out at night (except for those cheaper movies where the sun is still out...).
Full moon can occur for several nights in a row.
Eclipses happen frequently, and without any warning.
EVIDENCE
Incriminating evidence can be found either as photograph number four in a stack, or in the next to bottom drawer.
Be sure to leave your important tapes, such as the one labelled "Incriminating evidence against Senator Smith showing him taking $24million in bribes and then fondling the drug lord's daughter" or your computer floppy disks labelled "All the nuclear launch codes are on here" where they can be easily found.
All characters keep detailed newsclippings of important events in their lives, particularly those events that must be painful to recall, such as the loss of the character's immediate family due to their own negligence. NB: If the news report would have come out while the character was in jail or on the run, all the more reason for the character to have kept it intact.