People's motives can be varied but your three scenarios probably represent a reasonable spread!
I know, because I did it, if you want something badly enough, you'll find the money!
However, in the long run it would be cheaper to save and learn to fly full time rather than just do, say, an hour a week.
You also need to consider the costs of maintaining the licence and what you want to do with it once you've got it. I have no idea about drop out during a PPL(H) but post-licence, I believe it is quite a high percentage.
Cheers
Whirls