They feel bad about themselves. You will meet more of those people at this website but there are also alot of good sports here.
Can anyone explain

I admit I get annoyed sometimes when I lose a game to someone who appears to play much better than their rating. It seems like I'm losing more rating points than I should. I'll make a comment like "you play much better than your rating" which can be taken in several different ways. It's a bad habit of mine. I should know better: I might be playing a rapidly improving player, and a rating does not guarantee how well or not well a person will play in a given game - a 1400 player might play like a 1600 player or even higher. The bottom line is that many (most?)chess players are competitive, intense, and dislike losing. This can easily lead to bad behavior. Thanks for your comments.
Why certain people have to be sore losers on this site. I happen to play a bullet game with a person and I won both games and he wants to complain about how he was on the phone and I suck and blah blah my rating is 1429 and his 1702 and he was griping about how my rating is so low. Where's the sportsmanship?