In addition to the risk and opportunity cost and work-life balance issues that everyone's already mentioned: immature organizations. Both in the sense that the

In addition to the risk and opportunity cost and work-life balance issues that everyone's already mentioned: immature organizations. Both in the sense that the organization itself hasn't yet matured and that the people running the show are often immature. This is particularly prohibitive for underrepresented groups - a combination of colleagues too inexperienced to know what professional behavior actually looks like, nobody more experienced to model better behavior, and nobody to turn to when things go horribly, toxically wrong. The superfund site cases are thankfully rare, tho we've seen a few of them discussed here. Even some of the big names (Uber and GitHub come to mind) have hit the news with significant issues that have made employees feel marginalized. And that's just the ones that have made the news. Even if the problems are relegated to only 5% of the startups out there, that's a risk for a job seeker. Moreover, the weird kool-ade assumption that the team has to all bond and be best friends and voluntarily go out for beers twice a week as long as the company is <25 people is off-putting. Especially for those of us who are more than 3 years out of college and already have friend networks and in many cases families we want to spend time with instead. I would also mention that there are some things startups are great for in terms of learning, especially as a junior. You get exposure to a lot of things, the chance to wear different hats, challenges that in a larger company you'd be sheltered from by the presence of seniors. But a very small company isn't always great for mentorship, especially in management. (My experience with management at early stage startups has been awful.) Even when management is excellent, startups are typically too small to have layers of management and opportunity to learn leadership and management skills. Further, startups tend to be devoid of opportunity for advancement or promotion within the company unless they manage to grow very quickly - which is rare. And when they do grow quickly, they typically grow too quickly to grow well. Hiring too quickly to preserve culture. Outgrowing processes and then taking 18 months to realize it. Hiring incompetents or toxic personalities because they can't find enough bodies to fill the seats at the at-best-median salaries offered. And then there's the inevitable 18 month long "we'll be out of runway" death march. Never again.