I wasn't going to answer as I have no idea or expertise and there are probably a lot of important characteristics that are important. But the first thing that came to my mind is patience. I just see those guys standing around (don't take that the wrong way- it's a busy tough job) on the driving range while their player hits balls. To cater to and follow someone around - it seems to me it would be easy to lose your cool. Plus - your both in the game but you don't get recognized most of the time. That makes me think- why don't they and wouldn't it be a nice segment to interview the caddy after the round, etc.
__________________
Life Goal- Developing a new theory of movement based on Brain Science
Interests - Dabbling with insanity
Hobbies- Creating Quality