I've seen companies raise single digit millions and not even get close to $1M in revenue, over 5 years later. The result is founders have been diluted massively after a couple of down rounds. Meanwhile, preferred dividends are accruing year after year. The odds of a big payoff gets smaller and smaller the longer this goes on.

Odds are you'd make more money taking a job at BigCo, live like you only needed half what you're making, and invest that extra money into the public market. This isn't as fun though.