Y Combinator likes to fund startups that grow organically out of their founders' lives. If you really want to understand YC, read this, which explains how YC grew out of Jessica's.

I haven't read this since Jessica wrote it in 2018, and I'd forgotten how good it is. There's so much in here that I had a really hard time choosing a quote to post with it.

“Growing the Puzzle Around You” by @jesslivingston I read it at least once a year.