Coherence means that the whole is greater than the sum of the parts.

Coherence can be cheap ("automatically cohering") or expensive to create.

The expensiveness of the coherence is how much effort must go into coordination to get a coherent result.

Coordination gets super-linearly more expensive as the number of entities that must coordinate grows, which means a non-automatically-cohering thing gets more and more expensive as it grows.

At some point a non-automatically cohering thing will hit an asymptote where all energy goes into coordination and none goes into net-new value creation.

In contrast, automatically-cohering systems instead have a compounding loop of value. The faster they go, the more value that is created, at an accelerating rate.

Things that make something more automatically cohering

A shared north star

Independent components with clear boundaries, where it's OK for that boundary to be visible externally (Conway's law)

Ecosystem (relying on third parties to create some of the value)

Network effects

If you base your value proposition on polish and coherence of your product suite, then it will not be automatically cohering.