All of that started with Twitter... I created an account on Twitter. My way to Twitter was quite long and there were, I guess, 3 major factors that made me do that: changes in my professional life, Bob Walsh's comments about Twitter and Hanselminutes episode about WPF Twitter client blu. In my 2 or 3 days Twitter "career" I've already seen famous "Something is technically wrong" so I can see myself as an experienced Twitter user.
But there are 2 other things that prompted me to think about software quality.
After listening to Scott Hanselman's podcast I installed blu. The second thing I noticed after slick UI was inability to work through proxy. I live and die by personal proxy which allows me to easily migrate between different networks during my day. So, what can I say? Nice piece of software, but almost completely unusable in my setting, which as I would guess is not uncommon.
Another sad experience is twitbacks. As a newbie I given in to temptation of working on form rather than the meaning first. I've spent quite a time with this tool, but was not able to produce any sufficiently good looking background. Main issue for me was strange resizing which made text blurry and also lead to incorrect alignment with functional elements of the Twitter page. Again, nice idea, but not usable.
Both of these cases look to me as an obvious shortcuts taken by the development teams on requirements definition or testing stage. Quality of the system output is determined by weakest link in the system. Determined to the extent that piece of software may be rendered unusable in certain common scenarios.
Network client solution cannot omit widely spread variances in Internet connectivity settings.
Image generation software can not afford generating funky images.
Check that you have not fallen into the same trap or start fixing that immediately.