I've been self-employed now for over 30 years, but I remember my good and bad bosses from the six years I had a formal boss.

Since being self-employed I've had hundreds of "bosses" (clients) on each project and/or contract. There are the good, the bad, and the ugly.

Bad bosses are like failures. We can often learn more from them than from the good bosses and successes.

I take mentors out of that equation. I was very lucky to have several great mentors and a few role models in my first job out of college. I learned a career's worth of insight from fewer than 10 people through several intense projects. I was very lucky.