I had to look up the meaning.
Counting coup was considered a greater honor than killing and scalping an enemy. Warriors would often not kill the enemy if they were already in retreat and didn't want to waste ammunition.
Warriors would receive an eagle feather if they returned from counting coup unharmed. If they returned wounded, the feather would be marked with red pigment.
Counting coup was also used in battles against American troops. For example, at the Battle of the Little Bighorn, a Northern Cheyenne warrior and his friend counted coup on a soldier with their whips and grabbed his carbine. They didn't kill him because they didn't think it was particularly brave and they didn't want to waste bullets.