I think 1 of the reasons is that he can be a real asshole outside the ring. I seen videos of him calling all his past opponents pu##ies and fuck this and fuck that kind of attitude and people in his entourage don't help his image either. Do you think Nike would endorse Tiger Woods if he called all his opponents on the PGA a bunch of sorry motherfu##ers? He is an awesome fighter that just needs to keep his opinions behind closed doors and away from the spotlight if he ever wants 1 of those big endorsement deals. There is nothing wrong with being humble.