People who say that they can fully control their emotions and they dont get angry when they lose, I think they are not 100% honest with us. Of course nobody likes to lose, but many try not to show their emotions, even to theirselves. Somewhere inside, they get angry about losing. Difference is in a way they express it. Even being sad or disappointed can be considered as a light version of aggression. I do get angry when I lose, it is ok to be disappointed with wrong result. But as a calm person, level of my anger is very light; I prefer to curse/say bad words.