I've always thought that the talk to customers advice was bad as a starting point. If you don't have the domain experience to go to your first customer and say

I've always thought that the talk to customers advice was bad as a starting point. If you don't have the domain experience to go to your first customer and say I built X and it solves your problem Y then I think you're barking up the wrong tree. Once you have customers it becomes important to talk to them for improvements. And when you have a product obviously you've gotta talk to people to sell it.