You just have to hope for the best and if it doesn't work out you get lectured by some smartasses that it's your own fault.
Like the other lies the moneyed interests tell, the belief that it takes a fresh young generation to build good products and that's why the oldest guy in a random SV startup is 26 is pure propaganda that they're hoping you won't see through. People take this bait and go out and work for a free room in an apartment shared by 6 other "founders" and a laughably small basic living stipend that doesn't even equate to minimum wage.
Maybe a few hundred of these people have actually ended up getting rich? And they're "founders". How many early startup employees are doing well right now anyway? How much have Dropbox's first 50 gotten, for example, and how does that contract with dhouston's take-home? The early employee race is really baseless.
It's a fool's game, and people realize that after a couple of years, and then go work at a real company, where they can at least collect a market salary and where prudence and experience aren't plainly mocked and discarded [because these attributes threaten the people at the top].