I've made quilts I don't like. I see quilts I don't like, but luckily a comment isn't always expected.
If someone asks me for a critique, I won't hold back but will give my opinion on how I would have solved the problem, ie 'you know, I might have..' I don't think it is necessary to insult someone's work to critique it.
If someone shows me a quilt to admire, I find something to admire.