Comment by nine_k

A family is small enough to allow for reasonable planning. (Imperfect still, as you know if you ever tried to run a family.)

Indeed, a private company usually operates in a way a centralized monarchy / oligarchy would operate: the bosses determine a plan, the subordinates work on implementing it, with some wiggle room but with limited autonomy.

Larger companies do suffer from inefficiencies of centralization, they do suffer waste, slowdowns, bureaucracy, and skewed incentives. This is well-documented, and happens right now, as we facepalm seeing a huge corp doing a terrible, wasteful move after wasteful move, according to some directives from the top. This is why some efficient corporations are internally split into semi-independent units that effectively trade with each other, and even have an internal market of sorts. (See the whole idea of keiretsu.)

But even the most giant centralized corporations, like Google, Apple, or the AT&T of 1950s, exist in a much, much larger economy, still driven mostly by market forces, so the whole economy does not go haywire under universal central planning, as did the economy of the late USSR, or the economy of China under Mao, to take a couple of really large-scale examples.