1. Asking for advice early enough - you're bullish when you're young. Often young entrepreneurs don't leverage their advisory board often enough as they feel they have to prove themselves on their own steam.

2. Focus - they get torn this way and that by new opportunities.

3. Emotional maturity - I wrote an article about this: http://startuphat.com/seasoned-entrepreneurs-curb-their-enthusiasm-and-depression/ - mindfully navigating the troughs and crests of one's emotions is a critical trait that needs to be cultivated.