William Gates III was incredibly lucky, to graduate from High School with millions of Trust Fund money, and friends such as Paul Allen who enjoyed similar good fortune and were willing to join with "Trey" in founding Microsoft. Trey's first choice of co-founder from High School died in a mountain climbing accident.

There was also the luck of Trey's mother being on the National Board of United Way of America at the same time as IBM Chairman John Opel.

http://www.nytimes.com/1994/06/11/obituaries/mary-gates-64-helped-her-son-start-microsoft.html