How important is domain expertise in a startup?
Some people say that it's important to know how to lead. Yet time and time again, we see people go out of their domain expertise to start something completely irrelevant. Example being Jeff Bezos and Elon Musk starting a rocket company, and Richard Branson starting an airline.
Isn't a broad overview of the underlying business and technology enough to lead a great team of experts?
Those guys pay alot of other people money to do the heavy lifting. Their businesses took a while to become profitable. For a solo dev/designer or small team that wants to make money it's best to not go too out of your element in my opinion.