I probably would say it's QTE's. In a cutscene I want the option to go away and get myself a snack or a drink and not come back to find myself killed and I have to start over (I'm looking at you Resident Evil 4) I have actually rarely seen QTE's implemented well, one of the few times it has, it has been "Resident Evil: Umbrella chronicles" and "Resident Evil: Darkside chronicles" and I think the reason for that, is because it is a rail shooter and it is nice to get away from the monotony that can come from just shooting things. An example where I think QTE's are unnecessary is in "Resident Evil 4" for the reason I have stated above.