User blog comment:Supernovalm/The return of Sabo marking the start of something special?/@comment-5387880-20131213125401/@comment-79.107.37.109-20131214055550

I think the answer is obvious dude :P

Ace and Sabo during their teenage years were under WB and Dragons protection.Luffy was trying to chase his dream by his own and he gathered a totally unexperienced,talented though crew.Obviously,Sabo and Ace had better chences to improve themselves than Luffy.