Attempting to make established villains sympathetic anti-heroes.
Texas Chainsaw 3D and Maleficent are my usual examples of this. I don't understand the logic behind trying to make us feel bad that an angry mob gunned down Leatherface's cannibal family. The movie plays it like justice was done now that Leatherface got his revenge. And I was cool with Maleficent just being evil and petty. Didn't need that whole "no the king is the real evil guy" thing. They even made the three fairies shitty just to make Maleficent seem better by comparison.
Also, misunderstandings that could be easily explained with a single sentence but for some reason the characters feel the need to drag out the drama by instead saying things like "you don't understand" and "let me explain." Just TELL THEM. You're wasting all of these chances to explain yourself to tell them that you need to explain yourself. Instead of saying "you're making a mistake," maybe say "I didn't kill your father."
And very specifically, stuff like that moment in Paranormal Activity 3 where they got blatant footage of a ghost attack on camera and the guy's brother was slashed across the chest but the wife refuses to look at the footage. The footage was basically playing behind her but she's like "nope, nope, this prank's gone far enough." What prank? You think he altered the footage that well? In the freakin' 1980's?!