Here are my reasons, in no particular order:
1. Business & Money
To be a webmaster obviously you want to make cash.
2. Friends & Contacts made
I love the people that I have fun with who also have an excellent sense of humor.
3. Sense of achievement ie. building
I consider freesite building targetting search engines and so on, an asset building, revenue generating machine.
4. Freedom to work my own hours.
For someone as independent as I am, nothing beats this business for me.
5. Learning about the business
I've always considered myself to be a sick pervert but then I came here and realized that I'm quite angelic compared to some of you freaks.
6. Having Fun
All work and no play yada yada yada.