Sam Altman himself failed with his original startup (Loopt), then got hired into YCombinator. He's basically made it through leveraging his connections (OpenAI was a later investment with a number of other established players).

So really the advice is, be born into the right family, or at least get into to the right university, join the Good Old Boys network, and fail upwards. The old "two dropouts in a garage" idea of a startup immortalized by Steves Jobs and Wozniak is very much a romanticized 20th century phenomenon. Nowadays it's more like the old East Coast financial world of clubs and school ties, albeit with a different uniform of jeans and hoodies.