Like, superhero origins. Mad scientists have some obvious ones -- rebel against the maker of course -- but if that one doesn't sing, well, creating a superhero does not have intrinsic plot value. Develop the powers and the character, and it will gain one, but that's a heavy slog sometimes.
Or being given powers. There's intrinsic character development there, as the character copes, but you can't just cope. And you can't just go flying about or blasting boulders, or picking up trains. The powers need to be put into action. (And the donor's motives can be dragged out in the process.)
