Basically, it sucks to be an early employee in a startup that does not yet have traction ("product/market fit", in Marc Andreesen's words). You take on most of the risk of a founder yet have nowhere near the reward. And the hours are often founder-like as well, since the company often has no clue what it's doing and so you just keep doing everything until something works or you run out of money. And if you do run out of money (pretty likely), nobody knows or cares about what you did, which can hurt you in your future career.
Being an early employee in a startup with traction can be a very nice place to be, though. Many people underestimate both the chances of success once traction's been achieved (high, even if you're not yet profitable) and the potential market size. And you don't have to put up with the uncertainty and risk that the founders did. Most startups with traction don't get sold for $10-50M that's common for a startup with a product and a couple customers, they get sold for $200M+ or they go public for $5B+.
Basically, it sucks to be an early employee in a startup that does not yet have traction ("product/market fit", in Marc Andreesen's words). You take on most of the risk of a founder yet have nowhere near the reward. And the hours are often founder-like as well, since the company often has no clue what it's doing and so you just keep doing everything until something works or you run out of money. And if you do run out of money (pretty likely), nobody knows or cares about what you did, which can hurt you in your future career.
Being an early employee in a startup with traction can be a very nice place to be, though. Many people underestimate both the chances of success once traction's been achieved (high, even if you're not yet profitable) and the potential market size. And you don't have to put up with the uncertainty and risk that the founders did. Most startups with traction don't get sold for $10-50M that's common for a startup with a product and a couple customers, they get sold for $200M+ or they go public for $5B+.