"If not you, then who?" The ultimate guilt trip! I just despise this quote. Here's why.
It is a manipulative challenge. It is basically saying, "You are the last person left. We don't see anyone else on the horizon that will do it. And since we don't, you either have to do it, or tell us who can." You have to recognize your limitations on time, energy, and talent, and that just because there is a need out there, it is not necessarily true that because you are asked, you are the one to do it. Our culture encourages us to over-commit, creating harried, exhausted, frantically weary people. Even great saints recognized the need for relaxation, refreshment, and down time. So a legitimate answer to the challenge is, "No one." How about that! Mother Teresa didn't sacrifice time for morning prayer or evening fellowship to do that pressing need that never goes away. You can say no, too.
Another reason: You have to ask yourself, "What it is about this service request that no one else wants to do it?" Granted, there are services that take a compassionate and humble heart to get done. But I am always suspicious that the thing being requested isn't getting done because it just isn't necessary. Jack once heard on the radio a plea to donate money so that no kid had to start school on the first day without new clothes to wear. His first reaction: Aww! Who would send a kid to school in September without new duds? Then it hit him. We do that! A middle-class family, trying to make ends meet, and we sacrificed new clothes for school. I know our kids never suffered much from it either. So when you are pressed to do something, ask yourself, "Is it even worth doing?" This is another thing to which you can often say no.