I disagree but want to explain why.

I don't view GitHub as a place to show off your code, or a place to find new code, or whatever. It's where my code is stored. I trust what's on GitHub more than I trust what's on any server, or any laptop, or running on my dev environment right now. As such, the idea of "cleaning it up" before putting it on GitHub seems backward. Code gets committed as soon as it's written, and if it gets cleaned up that history gets saved too. If somebody wants to pull my shitcode down that doesn't even have a readme, that's on them.