What motivates an investor to say "yes"

I read a wonderful article by Tim Westergren, founder of the popular music service, Pandora yesterday night. Wanted to capture the key points...

What causes an investor to shift from looking for ways to say ‘no’ to looking for ways to say ‘yes’? The shift happens when three things come together for the investor:

1. They personally believe in the entrepreneur(s);
   
2. They have a sense (and it’s often just a gut feeling) that the idea could be very big; and
   
3. They have a personal interest or background in the industry that gives them a leg up the diligence curve.