Be suspicious of any work that is not building product or getting customers. It's easy to get sucked into an infrastructure rewrite death spiral.

AirBnB spent 5 months interviewing their first employee, before they hired someone and in their first year, they only hired 2 people.

It really is true that you become an average of the people you spend the most time with.

If you want something in a deal, just ask for it.

A third advantage of mission oriented companies, is that people outside the company are more willing to help you.

Unpopular but right is what you're going for.

If you're not in college and you don't know a cofounder, the next best thing I think is to go work at an interesting company.