Nervous about joining an early stage startup? Let's talk about risk. There are two types of risk: job risk and career risk. People think they are the same. They aren't. They are very different.
Startup COO job boils down to this:
1. Pick a problem area, and build 0 to 1 yourself. First principles get you pretty far!
2. After it gets going, start recruiting for an experienced leader for the area.
3. Onboard the leader well, nuke yourself out and attack next problem.