My dad is a decent 4.0 player and I always watched him play when I was little. I wanted to play tennis just like him, and at 6 I took my first lesson. From then on I have loved the sport. Another reason why I played tennis is that I wasn't exceptionally quick or athletic as a kid, but I was a good ball striker and had good hands at the net.
I quit tennis for about 4 months to play basketball when I was 9 (my parents were big believers in 1 sport at a time), but once spring came back around I just had to pick up a tennis racquet again. From then on it has been all tennis and to this day I can't think of much I would prefer to do than practice. Now if I could just figure out how to enjoy competing I would be in business!