These quality issues become a problem sooner than I would have thought, and Linux is big enough that they can just demand contributors know their stuff. But I found that in between "hobby project of my own" and "huge project where people beg me to contribute", there's a big space of "big enough that it gets contributions, but small enough that it's not worth turning contributors away for small quality issues". And I love that hub + `git am` lets me take those contributions but still maintain the workflow I want on the project.