What really annoys worries me about Windows XP are its silent failures.
I've been using XP Home edition on my personal laptop for about nine months, and I've been using XP Professional at work for four or five months. During this time it's had its little quirks, annoyances and, I'll even grant, it's moments of brilliance and overall I've learned to tolerate it as an operating system, maybe even learned to like it in some ways.
However the one thing that has really made me reserve judgement on it are the silent failures it seems to have at the quirkiest of moments.
What do I mean by silent failure?
I mean all those times that you try to do something, and nothing ever happens: there's no visible feedback, there's no error message, and most of all it just doesn't work.
As an example I regularly use two different applications as part of my job, to protect the (mostly) innocent we'll call them app A and app B. Now I really use these, push them hard and so I've discovered a couple of sure-fire ways to crash them both, this isn't a real show-stopper because both apps have more than one way to accomplish these particular tasks, so I can just avoid the problem and try it the other way.
The thing is that I discovered all of this running the apps on my Windows 2000 box. When app A crashes on my old Windows 2000 box its screen image freezes up, and then 5-30 seconds later up pops an error message, such as "App A: invalid aaaa to bbbb in cccc. [OK]", so I scan the frozen screen image to double-check the reference that I was working on, click [OK], restart the app and carry on working from that reference again. App B's crashes are similar, except it also writes something to the Windows error log as well as giving me an on-screen error message.
Under Windows XP the crashes are slightly different, I'll be happily working away in the app, then, without thinking, I'll click the button that I know will crash the app, and just as the ONM hits, the app just disappears from the screen. No frozen image left on-screen. No error message. No feedback whatsoever, its like it never existed. There are even a few tasks within Windows XP and Explorer itself that can trigger this behaviour (such as assigning groups in the ADS rights to folders and shares in the NTFS file system on a server through the local Windows Explorer) so its certainly not just a problem with 3rd party apps.
I'm sure when the Microsoft programmers demoed this to their managers that everyone starting giving out mutual back-pats and congratulations, "Look, no error messages, so no one can complain any more that Windows is riddled with bugs and freezes all the time!"
Unfortunately no one stepped back from the whole self-congratulatory circle w--- and thought, "Well maybe people will want some feedback when jobs fail? If only so they have a clue what to do/not do next time?"
It's a triumph of marketing over common-sense, and it really signposts some of the thinking behind a lot of Windows XP's interface and features.
If they don't absolutely need to know it, or it might make us look bad if they see it, then hide it from them at all costs.