What "quality" means with respect to software is something that the experts (Watts Humphrey, SEI, etc) leave up to the imagination, as if "quality" had a single, easy to express meaning. But it doesn't. That's why we need articles like this one. I don't happen to agree entirely with it, as I think that "quality" can have goals in tension with one another, like the "Good/Fast/Cheap, pick any 2" triangle of quality. But overall, a good article.