When you have done something good and helped someone, don't be foolish and expect a third reward on top of it. Don't expect praise from others or future favors in return. No one gets tired of what benefits them. Every natural action benefits you. So don't get tired of doing what benefits you, especially when it also helps others.
When thou hast done well, and another is benefited by thy action, must thou like a very fool look for a third thing besides, as that it may appear unto others also that thou hast done well, or that thou mayest in time, receive one good turn for another? No man useth to be weary of that which is beneficial unto him. But every action according to nature, is beneficial. Be not weary then of doing that which is beneficial unto thee, whilst it is so unto others.