I can think of a few reasons why you might have asked that question. One is because maybe you want to know that she is in the helping field for the right reasons, that she generally cares about her clients and enjoys helping them rather than just thinking you are just a job to her. Another reason could be that maybe you are just curious why she chose to go into the helping field. You might also think because you share so much with T and you don't know much about her/him asking the question might become a way of knowing her/him better and maybe getting closer to her/him. I haven't really asked that question to my current T, but usually most people gravitate toward the helping field because they generally like helping people. Sometimes even they have a history like we do, so that draws them into the field also. I hoped this helped somewhat.