Chess Ratings

My son gets very upset when his rating drops. His coach encourages him not to play if he's in a bad mood or tired, because he doesn't want it to affect his rating. I told my son, "I don't mean to disagree with your coach, but I say forget about ratings, focus on improving your understanding of the game, and your concentration and discipline, both of which will help you in other areas of life as well." Ratings and $1.50 will get you a cup of coffee, like my philosophy degree.How important is your rating to you?  I know some players for whom rating is everything. I'm not sure why. Some have said they set a goal of achieving a certain rating. They play strategically, avoiding losses to lower rated players by picking and choosing only certain settings, pairing systems and time controls. Some tell me thier rating is important to them because they are a chess coach, and want to be taken seriously. Some openly admit it's all about their ego. They just don't want to feel stupid. I have to let go of my rating, because when it's all about the rating I end up hating to play chess. I have a rating that fluxuates like a roller coaster. But it always seems to go back up, as a friend of mine pointed out when I was depressed after losing 30 rating points. I find that if I continue to value the lessons learned from losses, even from much lower rated players--when my loss was just due to some stupid blunder--then my rating generally follows my actual playing strength over time. If I study, my rating reflects this.