One of the best critisisms I ever got was when I was showing a print of an old truck in front of a old building in a local tourist town to the group at a seminar.
I had gone to that town for a very specific shot then afterwords went wandering looking for grab shots. The shot in question was one of the grab shots. It was well exposed, decently printed, fairly well composed.
The critique came as a question. Paraphrased here, "what were you trying to express here?"
I couldn't answer the question.