Horror movie clichés.

The claustrophobic closeup. The worst example is that French film with the 2 girls, one is in the middle of a small living room and the killer can sneak up on her because the camera is in her face. Durp.

Lights blinking that wouldn't blink in real life like LEDs or incandescent, or fluorescent blinking in a way they don't in real life. Static on electronics receiving a digital signal. Takes me right of the moment.

A person with no motivation to do so, investigates a noise. A recent movie had some guy robbing a store in the middle of the night, hears a noise in the back and goes to investigate, he dies. WTF? Anyone robbing a store and hears a noise is going to skedaddle.

Flashlight dies and then magically turns back on right when someone else is in the frame for a jump scare

Person (mostly hysterical girl) running from killer who is walking, takes a short break when she thinks she's gotten away only to turn right into killer.

Almost inhuman killer survives being hit by bullets and cars and wounds by various weapons, but dies in a very simple, anti-climactic way.

"Looking into a mirror and seeing something behind them."
Or very similar...looking into a mirror, nobody is there...something falls down to the floor you pick it up and when you get up again and look into the mirror the murder is behind you

The flickering candle when going down into a dark basement where they hear strange noises.

Somebody walking up behind someone and grabbing them on the shoulder for no reason whatsoever, just for a pointless jump scare.

-The main killer is dead but we get a final shot of his hand emerging in frame.

Then you know to expect a sequel.

A variation on this is when the defeated killer/monster appears dead but springs back to life one final time as the survivors are examining the body.

Then there's the long drawn-out sequence of someone walking down a hallway, down some stairs or towards a door, accompanied by tense background music. A jump-scare just waiting to happen.