OH! I was just thinking about this yesterday! The only one that angers me to an unreasonable level.
Redemption arcs!
I loathe them. Rarely done right, many times just absolves the villain of any blame or punishment, or even worse, they do the whole noble sacrifice route. You can be a piece of shit all you want, as long as MC forgives you, hey it's all good. It doesn't teach you to be a good kind person, it teaches to be a soggy wet foot towel and to allow every sick inducing person into your life.
It's present a lot in manga and eastern comics in general so I believe it must be tied more to the cultural and hierarchy norms of the societies the authors came from, but it's not restricted there. Oooh no, it's every kids show ever, it's most young adult stories, it's in a lot of videogames.
Want some Examples?
Naruto: Saskue should have been convicted or at least exiled for everything he did.
My Hero Academia Shoto's dad didn't learn anything, he's getting to have his cake and eat it. And that's because Shoto proved to be a better man that his dad ever will be. Lazy tho', since in truth he could have went his own way and be fine. I'm expecting a noble sacrifice redemption in the future 
Erma You can find it on this site. At this moment it's going through its villain redemption arc after being set up for ages. Yay want to live peaceful into your old age after you mentally fucked up your whole family? Sure knock yourself over, all is good. Still ongoing but I'm expecting another having your cake and eating it scenario.
World of Warcraft Sylvanas the sexy ex-elf, is being set up to be slapped about a bit in a raid then given a redemption arc after mass genocide, treason, causing a war and if you've read the BFA prequel novel, going all terrorist on her own forsaken. "But muh good side wus stolen!"
