why do we work with animals??

some days it makes me wonder why we choose to work with animals. i milk cows and don't like getting muck on me, so why do they decide to take pot shots in getting me covered, in muck, instead of doing it on the other side of the dairy. then you get sheep who can have brains when they want, or it's a case of one goes the rest follow. then still don't go where you want them to.
it's a fantastic feeling when you work with a young animal, and are there to watch it grow and progress.

what makes you work with animals??