One thing that's not discussed enough in the context of employees compensation (especially early ones) is prestige. Many people join startups because of the promise that that company will become the next Google. They see peers who follow the same logic (Marissa Mayer, the PayPal Mafia, any PM at Google in the early 2000's, etc) and see what fame, riches and following those people gain as a result of being part of the early days of a massively successful company. This is also why YC companies categorically can attract better talent, because even if the company fails, you can still tell your next potential employer you worked at a "YC backed startup". It's almost the equivalent of a Stanford degree. So, if you're an employee of a company that is already vetted by a number (i.e. amount of funding) of well-known backer (i.e. YC), you're risk is massively reduced given the insane amount of recruiting opportunities available.