Write something better yourself...!
Many years ago, I was performing in a concert where a person of great authority was the featured soloist. The concert was not a success, and I was very surprised when the soloist later asked for my opinion on the performance. What could I possibly say that would not offend? At the age of eighteen I was an even worse liar than I am today. I mumbled and stalled - eventually coming up with the more or less true statement that I didn't really care so much for the piece that had been performed. The reply was: "Well, if you don't like it, write something better yourself!"
Next time we met (about a week later). I presented this person with the piece in the attached video. Needless to say, it didn't go over that well...
Are there lessons to be learnt from this?
1: Don't be a smart-ass
2: It is easy to find faults with pretty much anything. Keep your mouth shut and do come up with something better yourself.
3: Don't ask for feedback if you don't want it - especially from a teenager!