There is sooo much:
1) I have horrible allergies, this is one of the only things that will get me outside, I still suffer, but I enjoy the suffering much more than just hanging out or walking outside
2) My wife enjoys it too so it is something that can always be suggested with little chance of veto.
3) Like others have said, watching the disc do what you wanted is a beautiful thing. It is like gambling 50+ times a round and sometimes you hit the jackpot, other times you crap out.
4) The unpredictability of said flight, especially when trees and other nature are brought into play...trees can give you some lovin you would never dream...they can also beat you like a stepchild.
5) Nature. We saw a baby dear yesterday at East Roswell Park. There were 2 women on my card so I had to tell them to snap out of it or they would've stared at it all day! Have also seen bunnies, woodchuck, squirrels of course, a hawk, an owl etc etc...
6) It is something I am "ok" at and enjoy doing and having a really good round is very satisfying.
7) We just got into the tournament scene and really like it.
8) Awesome people, CraigD and family, Gvan and family, 12StonesScott, ATL Scott, Lewis, David Sauls and many others not on this site make the sport worth playing.