True he had some ability, but nowhere near as much as he believed himself to have!!! The physical side is only half of what is required to be a great. Look at all the great fighters through the years and look at their training commitment. It would be a nightmare to try and train Zab. Also the main reason I dislike him is for his attitude and mouth outside the ring. If he could only back up half of what he talks then he would have a run at being the greatest P4P of all time.
Case in point: look at the interview he gave with "His Homeboys" before the Baldomir fight. His father added a contribution as well. It was totally disrespectful to another fighter, even if he was several leagues below him. But then to go and loose to him?!? For someone who got comprehensively beaten by 3 fighters he still talks a huge amount of sh*t before fights.
Typical bully, likes beating up on people who are a lot lower than him, but can't perform when the field is equal and go on to make excuses/throw tantrums/resort to dirty tactics when things go against him.
PBF may be arrogant and talk big, but he works damn hard in training to make sure that he can back it up. That means that it isn't arrogance but confidence.