This was a tough question to formulate and I probably did a poor job with it.
But there were several people who gave them breaks and there were several times they nearly called it quits.
Epstein and Martin were clearly huge breaks, but did they make John, Paul and George's first goal a possibility (to be able to play music for a living?)
There are others who come to mind in terms of giving them critical breaks, like that Cass and the Casanova guy, Bob Wooler, Mona Best, Allan Williams, and the owner of Hamburg's Top Ten Club.
The only one listed so far I don't agree with was Pete Best. While he hustled and did many things with his mom behind the scenes, I don't think they would have folded up shop had he rejected the Beatles' offer to go over to Hamburg in Aug. of 60.