The aim of a founder is not to be the best marketer or developer. It's goal should be knowing just enough to hire the best people in every field and lead the team. This what makes a great founder.
You're describing a great CEO, not necessarily a great StartUp founder. In the beginning the founder's job is not to hire people (you're not ready for that yet). It's to execute and demonstrate some sort of traction--the traction you can use to hire great people. Ideas are a dime a dozen. If you want to hire great people, you need to show that idea can be executed before you can hire "the best people in every field"
