so i was thinking about this recently and the only conclusion i can come up with is...after he fight pac, he'll have to retire for good. not from injuries from the fight, but...what's left after he fights Pacquiao? it's the only fight left that matters to his career. after that, he doesn't need to fight again. maybe he wasn't ready to fully retire yet. maybe he wasn't done making all that money. i think he knows after this fight, nobody would care who he fights anymore. so he's waiting until he's ready for it all to be over to where he can get the most money out of it and THAT'S when he'll step up to the fight. also knowing that Pac is going to be his toughest fight ever could be on his mind, but i don't think he's scared. he's just not ready to leave yet...
Boxing needs a awesome long-term rivalry from them, unfortunatly I don't see that fight competitive enough anymore. Mayweather fights him, and wins decisively if they fight at all.