I ran an Aliens rpg years back. But the players didn't KNOW it was an Aliens game until halfway through the first session.
They thought it was a sci-fi game but they also thought the monsters were going to be zombies.
Over a period of 2 hours they then proceeded to make EVERY Aliens movie cliche "mistake" known to man. Because at the time they all made sense.
The characters in a story don't know they're in a story or what kind of story it is.
They might think their in a romcom instead of a slasher movie. And if you're not in a slasher movie, why the fuck would you search through every closet in your house just because a cup mysteriously fell off a table in the dining room?
Characters in a murder mystery should have some fairly good clues they're in a murder mystery.
Though admittedly at least one character doesn't find out in time.
