I can accept that there are different levels of growth and at each of them there can be trouble. But it's not just one level. You can just as well stumble at 5

I can accept that there are different levels of growth and at each of them there can be trouble. But it's not just one level. You can just as well stumble at 5 employees (I experienced that), at 17 employees (experienced that) or at 80000 employees (experienced that; admittedly not a startup though).