And his lack of success says to me that he has come into his COO/CFO roles with the wrong attitude. If I can rephrase the question as an entrepreneur with his similar wording, I may say this:

“I was interested in your thoughts on when experienced Series B executives realize they are part of an existing team and culture that needs to bring an additional perspective to the ones the entrepreneur and other executives have at the company. The real smart ones that understand know that they are bringing their experience to an existing table and are not the next great hope of the company.”

It is the very difficult job of the entrepreneur to create and the equally difficult job of the “experienced help” to come into a startup and have the entrepreneur and the rest of the team want to listen and follow. The “real smart” entrepreneurs do not roll over and the “real smart” experienced help do not expect a handover.

So how to avoid? Your advice to your friend is fine, but that may test the social interaction of the participants rather than their working style. While it does not always work, I try to set up a few business scenarios (from mundane to difficult) that we can discuss (say, how to launch a difficult product, how to turn around a difficult but loyal executive, the merits of a particular go-to-market strategy) and see how the discussion goes. Do we reach the same conclusion? Do we reach different conclusions respectfully? Does one person always give? Do we give build on top of each other or do we debate?

It is unlikely we will be friends, but we must become great business colleagues