A good actor is like watching a great musician, but having a...

A good actor is like watching a great musician, but having a bad actor terrifies me, because it means I've got to find something to say or something to do. And that's really frustrating, because you want to be concentrating on everything, and instead you find yourself bogged down with helping someone know their lines or not bump into the furniture, and that's when you want to strangle them.