The first argument seems to reduce to the same basic idea entailed in expressions like "The first 90% is easy, it's the second 90% that gets you". Or "the devil is in the details". That I totally agree with. The seemingly trivial, small details absolutely add up and constitute a TON of working in getting a system into a truly "finished" and polished state.

But the second argument seems to amount to what I find to be a tired and inaccurate meme - "Open source software sucks because developers don't think like end users". OK, to be fair, some Open Source software does, indeed, suck at UI and usability, and maybe it is because most developers aren't good at UX. But by no stretch of the imagination does this apply to all (or maybe even "most") OSS, and also, it's hardly the case that proprietary software is necessarily better in this regard. Have you used, for example, Oracle's back-end / financials software? F%#@ that... Hideous (or at least it was last time I used it).

All of that said, this issue is near and dear to my heart, because this is something we think a lot about at Fogbeam. Luckily one of our founders is a designer and UI/UX specialist, so we have a leg up on some other open source projects. And while we don't have the clean UI and the awesome UX we want just yet, we aren't finished either. Our commitment is to absolutely nail User Experience, and be better than anybody else in our space, Open Source OR proprietary. Yes, we still have a lot of work to do, but that's the goal.