What motivates you?

Currently stuck in a summer slump (that I know will repeat during the winter) and am in need of some extra self discipline.

I personally am not motivated by much in general. I end up working harder if it’s something for the sake of my close friends or my little brother, but not much else.

What about you guys? Who/what motivates you? What are you aiming for? What do you tell yourself when you start to feel pessimistic and/or lazy?