[ansel12]

My pet peeve in Hollywood gunfights is cocking a gun. First, whoever has the gun waits until they are actually confronting someone else before they cock the gun.

Especially when they have been moving through the house for 2 or 3 minutes already, clearing it with all that high tension pointing of the shotgun, and then when they finally see the monster or the bad guy, they chamber a round, and you just go 'wait a minute, during all that tension filled dramatic searching through the rooms and up the stair case where only your supercool quick reflexes could save you, your chamber was empty?'

[Vince Ferrer]

That's exactly the cliche. At that point, cocking the gun is just trying to prove to the audience (and the guy they are pointing the gun at) that you're really really serious this time. But doing it then also proves you weren't serious before.

I also count the variation which isn't exactly this stupid, but still pretty bad, where the cops gather right outside the apartment door of a bad guy, and then cock the gun, once again for dramatic effect. But everyone inside can probably hear it, and think, "hey is that a bunch of police about to come bursting in here? Maybe I'd better get my own gun and be ready to shoot." How about getting ready earlier, like right after they leave their car, or in the elevator up to the bad guys? They never really know where the shooting may start.