“If you’re one hundred percent certain about something, you don’t really have any reason to work too hard for it. It’s already being handed to you, so there’s nothing to strive for. You go about your life, la-di-da, and wait for things to fall into place around you. Knock a few percentage points off that certainty factor, though, and you start putting real effort into things. You don’t get complacent. Not knowing what will happen next keeps you on your toes.”