All chess players have lost games. All chess players have lost games while being in a good position, maybe up some material. It is usually the most painful experience when you lose a chess game that you were winning just a move before. A little, tiny thing you do in one second can ruin previous hours of concentrated work and great amount effort put throughout the game.
The price of a wrong move is too high in chess. For instance, in basketball you can make a mistake, allow your opponent to score and you can keep playing and still have a good chance winning the game. In the game of chess if you drop your queen or miss a mate there is no way you can recover. Chess players are all different, but in one thing they all the same: no one likes losing.