One famous moment in GSP's career was when he spoke of how he was obssessed, almost addicted to learning new skills. This led to him developing one of the most diverse skillsets in MMA history. However, I noticed that addiction is a trait that is common amongst all great UFC champions. Cain Velasquez appears to be addicted to the grind, pushing himself harder and harder, showing improvements every time he fights; Anderson silva appeared to be addicted to testing himself, putting himself in compromising positions (e.g against the cage against Bonnar) that bring the best out of him. I'm not sure about the other UFC greats, what do you guys think their addictions are?