Mark.To answer your question frankly is that most people including artists do not have a teachable spirit, Most artists are like teenagers that always state that they are "with it".In other words they know all and nobody else know better than they do and cannot teach them anything. More than that.....most people do not know how to critisize or comment without sarcasm or hurting others.Comments should have a content of information or suggestion how to improve on any particular work of art,book,drawing,sculpture,....whatever. Here is the challenge! Put forward a photo of what you think is your best work of art you have done to date.I will then comment,at least try to comment,in such a way ,as written above,Perhaps the two of us could then learn why artists do not want any comments.