Although I'm an newbie, I'll do my best to answer.
Motivation: Alright, alright, I'll admit it's a guy!

But seriously, there's something about surfing that you can't experience with other sports. I fence and dance, but they don't have the same adrenaline rush like surfing does. You're based on solid ground whereas in surfing, you ride something that's moving. It's the unpredictability that's addictive. Besides, there's something bad-ass about being able to do a cutback on the lip of a wave or slice through a pipe.
Location, location, location: Since all I know right now is Taupo Bay, I'm biased.
Why did I start: *see first answer*
New location expectations: Right now, that there'll be small enough waves for beginners, like myself, and friendly kiwis to talk their ear off about surfing. Hey, I need all the help I can get! Besides, it's a good way to meet people and enjoy the sport more.
Hope that helps!