The emergent whole is often entirely unlike the individual parts.

One reason is that the collective emerges out of interactions of the parts.

You can't take a picture of a moving stream and hope to understand it.

But the emergent whole would still be hard to understand even if somehow interactions didn't matter.

For example, imagine every agent in a system has a small, consistent bias towards a certain direction.

For each individual agent, the bias is swamped by the overall specific details of the agent.

That means the bias in invisible when looking at each individual agent.

But at the level of the collection, all of the random details balance each other and all that's left is the consistent bias.

That consistent bias is now a strong force at the level of the collective.

It's a kind of Simpson's Paradox.

Examples of this kind of thing: It's possible--common, even!--for a group of extremely smart people to collectively act like a total dummy.

The thing that emerges can be beautiful and great; but the more common default is a slouching, invisible, all-powerful eldritch horror.