Greed has nothing to do with circumstance; greedy people may be rich or poor, old or young. When you are constantly trying to get something, you prevent yourself from giving. When you are constantly thinking about what you are trying to get, you limit or prevent yourself from giving. You only receive by giving, and the more you give, the more you get. As a Taekwondo instructor, you may be helping a student become a better competitor, only to have that student defeat you in the next competition. Is this a loss for you, or is it actually a gain?