Reminds me of my art class at college. At the end of our first year we each had to take our years work and go to see the teacher who was standing at the front of the class next to a large dustbin. He went through my thick pile of work one at a time chucking them in the bin, "No. No. That didn't work. No. What's that supposed to be? No. This one's okay, not worth saving it though. No. No...." Think I had about three pieces left by the end.
That kind of thing can be invaluable but I agree that it would be out of place on WAB. I'm all for constructive criticism and a little encouragement though.