I spent 15 years thinking I had fortitude. Turns out I was just stubborn. Pretty much ruined my life.

"Winners never quit, and quitters never win. But people who don't win and don't quit are just stupid."

I landed on my feet. Others won't be so lucky. (Ironically, I was only able to be stubborn for so long because I had so much good fortune elsewhere. If I'd had less support, I'd have quit much earlier, and maybe it would all have turned out better.)

The moral of the story: it's better to be lucky than smart.