In spite of being the foundation of the American fabric, I don't think that competition (defined as a contest in which someone else must lose for you to win) is a good motivator. You are often trying just not to lose, not necessarily to "win" and not necessarily to do something the best you can, just enough to "win". Fiercly competitive people often have low self esteem and often do not want to work cooperatively (since competition and cooperation are opposite.)
Check out "No Contest" by Alfie Kohn.
stephen
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