I became fascinated by transplantation when I learned that my great uncle was Dr. Thomas Starzl. My interest was mostly motivated by trying to understand what he accomplished. He did a truly maddening amount of research and with such a depth of knowledge that I get lost just trying to read some of his more basic contributions. Much more than the trivial medical knowledge I gained trying to understand his work, I appreciate the astounding dedication he had.
I think there is something beautiful about the combination between deep knowledge of the systems involved and the art of surgery. Working on systems that are nominally the same but with unique characteristics in each case is fascinating. The results possible when you fully dedicate yourself to a craft and the potential to snowball your successes is inspiring.