In duplicate bridge there are only three things more important than winning.
Playing the game right
Being fair and keeping your dignity (not cheating)
Being courteous. I recently was shushed by a player when I was making an important announcement. Another thing that happened was a player tried to say that he had pulled out the wrong card when he had made an insufficent bid. It was obvious that he was trying to pull a fast one.
It is important to maintain our honor, our sense of fair play and that we treat others as we would treat our family and friends.