Since day one. Someone has to manage, because there are resources and efficiency involved.
The hacker founder might not think of himself as a manager, because of the PHB stigma. But there's always management to be done.
I understand you didn't ask exactly this. You want to know when a "pure" manager should be brought on board. But if you realize that there're always things to be managed, the question becomes: Would this company run better if the engineers didn't have to manage? If they were free of worries about how much soda is left at the refrigerator, if the revenue/income ratio is sustainable, if John's productivity is better with one monitor or two, if there's money to buy these monitors, and if there isn't, when the budget will allow it, how to explain to John why the extra monitor will only come next month, actually research the monitors, price, negotiations with suppliers, the wall socket where it'll fit, etc...
IMHO, "pure" managers should join the ship when more work can be outputted with him onboard. BTW there's nothing wrong with "promoting" an engineer to management. S/he doesn't have to be a manager all day, and this person knowledge about the products will actually help with the management part.
But really, just mutate your question. It's not when, it's how.
The hacker founder might not think of himself as a manager, because of the PHB stigma. But there's always management to be done.
I understand you didn't ask exactly this. You want to know when a "pure" manager should be brought on board. But if you realize that there're always things to be managed, the question becomes: Would this company run better if the engineers didn't have to manage? If they were free of worries about how much soda is left at the refrigerator, if the revenue/income ratio is sustainable, if John's productivity is better with one monitor or two, if there's money to buy these monitors, and if there isn't, when the budget will allow it, how to explain to John why the extra monitor will only come next month, actually research the monitors, price, negotiations with suppliers, the wall socket where it'll fit, etc...
IMHO, "pure" managers should join the ship when more work can be outputted with him onboard. BTW there's nothing wrong with "promoting" an engineer to management. S/he doesn't have to be a manager all day, and this person knowledge about the products will actually help with the management part.
But really, just mutate your question. It's not when, it's how.