Background story: did a startup as a CEO+CTO. 100 hours a week, mostly because I had to play two roles. It seemed easier to find a CEO than CTO.
So we were burnt out. Sold the startup. Made 750% ROI in a year, which is a good investment. Planned to reinvest that money into startups for maybe even a 300% ROI.
The plan was to go CTO route and rely on someone else to play CEO.
It didn't work out - most people were decent at business skills, but terrible with product. Some could build a million dollar traditional business, but couldn't make it in the startup space - they were too cautious, too scared of committing, or wanted passive income. There people with sales experience, who are great at forming strategic partnerships with big corporations, but don't dare talk to the customer.
So that was a mess. I regret expecting others to do well when given the trust and opportunity, even if they had done well in the past. I regret following logic over instinct, and following people who were not "animals" like Paul Graham suggested.
I'm working on a startup now, but it's the unsexy idea I had 3 years ago. At least I get full control over product and customer development.