Anything that we do, first and foremost, is to please ourselves.
The message of the article pins their success on this core belief. And while circumstances may change with customers and investors over time, David's quote should be the mantra of every startup while they get going and look for direction. Smart people do good things not because they conform, but because they have the vision of something different.
Trying to figure out if you're right is hard enough when you're doing something new. There is no sense in clouding the picture by basing your decisions on perception. It's far easier - and more fun! - to stick with what you believe when navigating the backwoods of innovation.