Interesting thread! I agree with Jack, Leadfingers & particularly Steve. Someone once said to me after a song "Your singing's really improved!". She was quite embarrassed when she realised how backhanded it sounded, but I took it as a compliment. (Apart from anything else, I knew she was right - my singing had improved.)

I didn't mention it in the OP, but what sparked this off was getting some unsolicited criticism. It was sympathetically phrased - "nice song, shame about the bum notes", kind of thing - but I hadn't mentioned any bum notes; in fact I hadn't realised there were any bum notes.

It knocked my confidence quite hard. Going back to Jack's comment, I always thought I was in group 1 - I do practice & listen to myself & try to improve. Having mistakes pointed out where I didn't think I'd made any mistakes made me wonder if I'd been in group 2 all along - maybe my pitching had been off the whole time, and I never realised it because my ear was off. Maybe the people who'd applauded me at singarounds were just being polite, maybe they were thinking "shame about the pitching but well done to remember all those words"...

When I'd calmed down a bit (some hours later) I ran through the song again, more self-critically - and OK, maybe the pitching on those particular notes wasn't dead-centre perfect. So maybe the other person was right to comment & I'm just a little too sensitive.