So, today I was playing Mercenaries 2, and in the final scene, you MUST do the sequence 100% right, or you will die, and that, my fine friends, is crap, especially when I have a Stinger, and can just blow it up right there. There is a poster here whose name I can't think of, has a signature called "Press X to not die", and how right he is. I hate having to do this every single time I want to hijack a Tank or Helicopter. And it's really bad when it happens in a cutscene, and boom, dead.
Some games, like Resident Evil 4, work them in and it's fun. A lot of games do it entirely unnecessarily, though. I know it's to try to add variety to games, but some games should stick to what brought them to the big stage and work on that, rather than try to slap stuff on for depth without being able to pull it off.