In highly competitive environments, humans tend to adopt a "single executive" type organizational structure. In short, there needs to be a single decision maker who can set strategy, make decisions, approve direction and so on at at least the rate of the competition. Committee systems work fine when things are more steady state and there's less existential threat.
Nations almost all adopt an executive system because nations compete. The U.N. doesn't because Earth doesn't have to compete with anything else. Imagine a competitive interplanetary situation and you can bet the Secretary General of the U.N. would quickly gain significant decision making powers.
Collectivist market philosophies tend to be built on the assumption that there will be no competition internally and thus can be run by various committees. However, even countries trying to follow various types of collectivist ideologies ended up with single executive-types at the top, again because countries compete.
On the small scale, many indigenous tribal systems rely on a council during times of peace, and elect an executive (sometimes called a "war chief") during times of war.
The phrase "business is war" is particularly appropriate since most businesses operate like they're at war.