The entire point of joining a start-up is to 'play the lotto'. You are deferring salary now for a chance at millions later. You would not do it if the expected value was negative[0]. However, it's becoming more and more obvious to even freshmen undergrads that it's all a load of hooey.

Not only are the founders going to need to be super transparent with their finances to get good interviewees, but some other event will need to take place in addition [1]. That makes hiring good employees even more difficult, especially as the company grows.

This behavior by the current unicorns can be overcome, but man will it take a change in the funding ecosystem. Since the current crop already has two unicorns (Uber, Wework) with major funding rounds by a shady group (the Saudis), I really doubt the ecosystem will change for the better of prospective employees.

Like it or not, the wild west phase of tech is over. It is better to join up with the FAANGs at this point for most folks. The expected value of joining a start-up is unlikely to be positive.

[0] Yes, there is a sucker born every minute, but in general, that's the idea.

[1] Events like the prospective employee will require really good healthcare that only this company provides, or the prospective employee really really needs a job for some reason, or the prospective employee lives 5 minutes away, or the prospective employee really is super passionate about the idea, or the prospective employee is a good friend of the founders, etc. Each prospective employee you hire is also unlikely to share any of these events with any other prospective employee, and these events are likely to change over time.