I hate it how the bad guys needs to have some sort of tragic back story to explain why he/she became evil as if that excuses all of the bad things they do. Besides, even people with happy lives ended up becoming terrible people for selfish reasons and because they chose to.
Kinda the same with 's comment about a bland male protag who is weak and oblivious to the harem around him. It's one thing if it's a male, but it's even worse when it's a reverse harem with a REALLY dense girl.
Um.... oh, when a villain could actually kill the protagonist and instead they choose to go on a huge monologue about destroying the world and defeating them muahahaha, so they end up giving the protag a chance to escape and defeat them.
Tropes and cliches aren't the same thing. What cliche I hate, those harem stuff with the male protagonist being a bland, weak-willed, having no real opinions, never putting his foot down, somehow every girl and woman wants him but he remains oblivious to it all.