If you are early in your career and considering working for an early-stage startup (or any stage startup), consider the following points sincerely.

You are not being hired to "learn things” unless learning means solving their problems. Many folks I interviewed seem to have a strange view of learning as if it is like Brownian process. You can learn the rest of your life and don’t accomplish much. Learning == solving problems is a healthy starting point. This view doesn’t conflict with industry interests. In other words, don’t expect to be paid for learning things; you are paid to get things done.

Before interviewing, learn about the product or problem a startup is building or solving. Your time there will revolve around that. Consider yourself extremely lucky if you get to work at things you love. But you must be ok to do things you don’t terribly like. You don't have to "love it" to get it done properly. Be professional! Also, great jobs don’t grow on trees; you have to earn them!

If you don't value equity, you don't value the startup game! There are not many good reasons to work at a startup (fewer to start one). Equity and working in trenches at the frontline are the only good reasons I can think of. I feel that it is okay if you only care for "here and now" things such as cash in hand, as long as you don't take more than you deliver.

Startups may have money, but most of them usually do. But they are always short on time. If you tend to procrastinate, do not go near a startup. Everything must have been done yesterday. Speed is a virtue. Please consider again if you are laid-back and don't enjoy the rush. There will always be a rush, and deadlines may bring out the worst in people. And if you also have thin skin, you are in a hell of a pickle!

You may have to do a lot of work you were not hired for. No startup can anticipate your role there. You may have to become a generalist rather than a specialist. Startup hiring advice: prefer generalists over specialists.

Netflix got this right: Your workplace is, at best, your team, not a family. I won’t work with my family or friends since most will be terrible co-workers. Being part of a team means always pulling your weight and some more.

Don't go to a cricket field if you only care about batting. Your team will be better off without you, no matter how great you are at swinging a bat. In a startup, you may never get to bat and perhaps spend most of your time curating the pitch, watering the ground, and managing the gymkhana. You join for the whole game, not just for batting or bowling.