
I have had both an original Desire and now a One X - both decent phones, but HTC has a few problems. The most important ones from my perspective are:
Too many models, with too confusing a line up.
A habit of dumping the current latest and greatest phone (and its updates) for a new one too quickly - well within a phones contract lifetime.
HTC Sense - dump it, give us plain Android.
Carriers delaying (the already delayed because of Sense) updates, or simply not providing them at all.
Give me regular updates and a bog-standard Android and I'd be happy. Yes, I know about Cyanogen etc. but this is about what HTC get wrong, not someone else gets right...