Koyama Shojiro, in "Shotokan Masters: in their own words":

"The most important quality of a successful karate-ka is commitment to everyday training and an appreciation of the mundane. Train hard, finish, bow, and say 'thank you' for the opportunity to sweat. The most important quality for a practitioner of lifetime karate is the ability to find such satisfaction in ordinary training. The successful practitioner of lifetime karate is successful because he has had a satisfying life, not because he is a tournament champion or 10th degree black belt."