How to hunt for a job?

Would you quit your job before you get another job?

What will be the main reasons for quitting? Pride? Dissatisfactions? Or just for the heck of it?

I quit my job before I started looking for another job. All 2 interviews I attended, asked me for reasons. I wrote clearly on the application form :

Reasons for leaving: Looking for career opportunities in other fields.

But, none believed. They asked, what's your REAL reasons?

Duh.....