I guess the parent means "do it for yourself". I open source my code under copyleft (generally MPLv2 or EUPL, I've come to like EUPL because it applies to SAAS) because I don't think I would make any money from not open sourcing it. By open sourcing under copyleft, I can potentially benefit from improvements by others.
I don't spend much time accepting contributions: I encourage people to fork. But if they make changes that I find interesting, I bring them back. For my benefit.
