You just haven't developed strong enough goals. Goals that will motivate and drive you.

Imagine you had mastery of PR, what would you PR?

See yourself in that state? Do you see people looking at you in awe at your amazing zest for speed and comprehension? Hear what they say. How does this make you feel. I bet it makes you feel on a high. Well then, consider this. If you work at it, these are the things you will achieve. Cultivate these feelings and use it as your driving force.