Basically we don't want to waste time getting into fights over ruffled feathers.

Here's the crux:

So why do we do this? The authors, not surprisingly, point to the incredible power of human groups, and our dependence upon being good standing members of them:

By confirming themselves more often than they should have, the inferior member of each dyad may have tried to stay relevant and socially included. Conversely, the better performing member may have been trying to avoid ignoring their partner.

Great instincts in general — except, of course, when facts and reality are at stake.

Nobody’s saying we ought to be mean to people, or put them down when they’re wrong — or even that experts always get it right. They don’t.

Still, I think it’s pretty obvious that human groups (especially in the United States) err much more in the direction of giving everybody a say than in the direction of deferring too much to experts. And that’s quite obviously harmful on any number of issues, especially in science, where what experts know really matters and lives or the world depend on it — like vaccinations or climate change.

The new research underscores this conclusion — that we need to recognize experts more, respect them, and listen to them. But it also shows how our evolution in social groups binds us powerfully together and enforces collective norms, but can go haywire when it comes to recognizing and accepting inconvenient truths.