Edit: Digging a bit further, it looks like the startup that he sold was Valet Gourmet which was a food delivery business in North Carolina and he worked on it for ~12 years. That's probably a bit longer than the tech startup timelines we tend to think of here.
That is something I learnt from my startups, running and selling them; things will take far longer and people quit way too soon. If you start a business, any business, thinking you will make fuck you money in 15 years is much more relaxed and better chances of success in my experience. Plenty of side projects I made over 10 years ago are still popular running on crappy tech and companies I co founded 20 years ago still exist and make profits. People think a lot changes but it doesn't; it changes on HN and Reddit but not the rest of the world even though the big changes like mobile happened; with a sprinkle of responsive over ancient html/css suddenly people use it again like it just launched.
Edit; in no way I want to imply to live on ramen for 15 years; live a good life all that time, but, at least in your mind, think the riches/exit will happen in a long time from now. It makes it all less bank or bust stress.