I struggle with this issue too. I point out the flaws in my own work almost without thinking.
In a way, the little imperfections make our work unique. There's no other quilt in the world that is the same as yours - even if it has the same colors, fabrics and the same pattern - it doesn't have those little 'mistakes' that make it yours (ours!).
I've begun to refer to those mistakes as my 'artistic signature.' ;)