Courtesy
 

Members are to conduct themselves in a courteous manner at all times. If you disagree with someone, attacks on someone's intelligence, knowledge or otherwise may be deleted and you could risk being banned. Matters of disagreement can be handled in a diplomatic way, no matter what the topic.

If you've posted for a critique and are hearing something you don't like, count to 10 before you write something indignant back to the critiquer. It can be tough, but you'll learn more if you remain open and curious rather than being defensive.