I guess I was thinking of the first few weeks/months of a startup where all the efforts are really around building the product. What does the business guy do? Definitely there are things to do, but if you had to dedicate all man hours to something, building product would be of paramount importance.
And when you think of technical founders like the Google guys, Bill Gates, etc, they started as technical and acquired the business skills as things developed. So yes, business skills are super important. But they can be acquired.
I'm not so sure that a business guy will just learn some technical skills in the early days of a startup. So the tech guy can learn business, but the business guy can't learn tech.
Ok, from a timing standpoint, I'd say that's fair. In my case, I've been hacking away, by myself, on the code for around a year now... and it's only now that I'm starting to get close to the point of wanting a "business guy."
That said, I think there could be a role for "business guy" even earlier in the process, depending on the details. If you're "scratching your own itch" and you know what you're going to build, then that's one thing. But if you're doing the "find a problem somebody has, and solve it" approach, then you could start the Customer Development process from day 0, and a guy/gal with experience in marketing / product management / etc. could be valuable then. Especially if he/she has some domain knowledge in the field you're working in.
I'm not so sure that a business guy will just learn some technical skills in the early days of a startup. So the tech guy can learn business, but the business guy can't learn tech.
I think it just depends on the individual. And when I say "business guy" I mean "business guy with some technical knowledge, particularly relevant domain knowledge." Which is one reason that finding the right person has been a challenge. I joke about finding a "used car salesman" and teaching them about software, but realistically, I'd like to find somebody who has experience selling enterprise software already.
And when you think of technical founders like the Google guys, Bill Gates, etc, they started as technical and acquired the business skills as things developed. So yes, business skills are super important. But they can be acquired.
I'm not so sure that a business guy will just learn some technical skills in the early days of a startup. So the tech guy can learn business, but the business guy can't learn tech.