The phrase that comes to mind is: A students become professors, B Students become executives at large corporations. It is the C students who--perhaps lacking the traits to succeed in the previous two pursuits have no choice but to endure the risk/hardship of entrepreneurship--endow professorships and name buildings.

Examples of this:

1. Founder of Kinkos (failed in school and had to repeat two grades)

2. Billionaire Flavio Briatore

3. Almost Billionaire founder of Jimmy John's subs

Another phenomenon I see often is what I'd call "The Video Professor". The founder of that company reaped a massive fortune teaching "dunderheads" how to use computers and operate simple programs like Word and Excel. Many of my techie friends would sneer and dismiss it as being "too easy" and fail to recognize the business opportunity therein or other many similar opportunities.