When People Refuse to do you Favors

Why do certain people seem resistant to any favors they have to do? Hey, can you throw this out for me? "No, why should I?" and the other issue, when you seem to be the go- to favor person. What should you DO? I say, if someone keeps resisiting favors and you are doing EVERYTHING for them, try to talk to them. Because, sheesh. That can get annoying.