Pondering my duties as a drill sergeant

Before today I never thought to wonder what goes through the mind of a drill sergeant as he shouts for recruits to stop being babies and keep going. The drill sergeant is never the protagonist in films or books. Sometimes he is the villain, but most of the time he is like a force of nature that the protagonist has to survive. But now I think that in the real world there are drill sergeants who have a deep sympathy for the pain of the recruits. The drill sergeants shout anyway because...