Clay Shirky on the collapse of complex business models:

In 1988, Joseph Tainter wrote a chilling book called The Collapse of Complex Societies. Tainter looked at several societies that gradually arrived at a level of remarkable sophistication then suddenly collapsed: the Romans, the Lowlands Maya, the inhabitants of Chaco canyon. Every one of those groups had rich traditions, complex social structures, advanced technology, but despite their sophistication, they collapsed, impoverishing and scattering their citizens and leaving little but future archeological sites as evidence of previous greatness. Tainter asked himself whether there was some explanation common to these sudden dissolutions.

The answer he arrived at was that they hadn’t collapsed despite their cultural sophistication, they’d collapsed because of it. Subject to violent compression, Tainter’s story goes like this: a group of people, through a combination of social organization and environmental luck, finds itself with a surplus of resources. Managing this surplus makes society more complex—agriculture rewards mathematical skill, granaries require new forms of construction, and so on.

Early on, the marginal value of this complexity is positive—each additional bit of complexity more than pays for itself in improved output—but over time, the law of diminishing returns reduces the marginal value, until it disappears completely. At this point, any additional complexity is pure cost.