This question concerns institutions - what makes a better institution. Under a hypothetical institution, we examine the marginal function of necessary evils after each additional coordinator is added. When this marginal function curve is smoother, we consider it a better institution; when the curve is extremely steep, we consider it a worse institution.

If an institution, when scaled globally, creates too great a burden of necessary evils for humanity, it's a failed institution. Most people would think of the state-planned economic system during the communist wave, with its bureaucracy, sacrifice of economic efficiency, and persecution of dissent - if such systems scaled globally, they would cause human civilization to regress. Clearly, most institutions lack strong scalability; when expanded to all of human society, humanity cannot bear the necessary evils of their expansion, leading to collapse.

One argument defends modern capitalism: The modern capitalist system, a union of corporations and states, can coordinate production globally. This is the strongest known and verified scalable system. This defends current social systems - capitalism is at least better than communism.

Another interpretation of what affects the marginal function is innovation. Innovation brings massive economic growth and social change. Continuous innovation creates new industrial interests and power spaces, keeping society in a fluid state, attracting humans to unite and move forward together.

There are many other explanations: law, language, information mechanisms, currency, culture, beliefs, and the recently popular 'autonomy and commons'.

Are there other answers?