I agree with this. What most developers, like me, love to think is that you can do "one more feature" and they will come, or another refactor, or anything. But I've learned this lesson. Building a startup us very little about coding, and more about all the other things that make up a business. What's your value proposition? How do you sell? How do you acquire users? etc... In the end, I've wasted way too much time on the things that didn't make a difference, but I think I've learned from this.