Not to beat a dead horse, but I think it is a personality thing.
While a few people who are at the polar opposites of the personality spectrum might need to "burn their ships" the vast majority of us need an anchor to keep us floating out into the sea of indebted/homelessness. And realisticly, for most up and coming traders learning the business, it would be easy to jump out to some mild success, think that you have the business & your strategy cold, only for the market to turn on you while you search for answers -- as well as lunch money.
The biggest challenge that I have hear over and over for inexperienced traders to cross over the threshold into savvy pros is knowing WHEN to apply strategies in a given situation. This along with recognizing false signals are skills that can only be mastered by trading day in and day out for a good period of time. It's the when & risk management that set you apart. Now how in the hell can you concentrate on the "when" you need to identify on your chart, if you stomach is wondering WHEN you going to eat next?
Seriously?