Experts: are some of them born losers?

On another topic entirely. I have been a keen backgammon player ever since I learnt to play more than 20 years ago, and when I bought a secondhand PC for my children to use (I have always used Macs, but because of schoolwork, they often need a PC for exchanging files etc.) , I was very pleased to discover that included in the XP operating system was a facility for playing other people around the world at backgammon. So ever since we have owned the PC and whenever I am at home, I have very regulaly played several games of backgammon.
The system invites you to gauge your playing ability. You can choose from beginner, intermediate and expert. I have chosen intermediate, which I think is about right. The system also tries to match you up with other players of the same skill level, but occasionally you are matched with a beginner or an expert.
Playing a beginner is usually quite boring and it is usually very obvious from the moves the other player makes that he or she is a beginner. What is amusing is when you play an 'expert', and remember the grading is always done by the player him or herself. The strange thing about the 'experts' is that all to often, and certainly more often than might be down to chance, they are extremely bad losers. If it is obvious that they are not going to win the match, they simply quit. That tells me an awful lot about a certain aspect of human nature.