Take a look to this infographic about the creation of Instagram, one of the most popular social networks.
Do you see something strange? Yes, the founders threw away a big part of their job. Twice in less than two months!
As Seth Godin1 wrote last week (in this post):
I find that it's almost essential to fall in love with an idea to invest the time it takes to make it good and worth sharing. And then, the hard part: deleting that idea when it's just not what it could be.The "hard part" is what makes the difference between a good product and billions of mediocre things out there.
If you don't trust me nor Seth, try to ask Robert.
Image taken from Founders and Founders (license unknown).