What we all say enough becomes true.

It's not obvious that this should be correct.

But we change our opinions on what to expect based on what we hear.

The things that happen coevolve their possibility space with what people believe.

If enough people believe it may happen (and take consistent, if minor, actions to prepare for it possibly happening), that makes it more likely to happen.

Small amounts of variance individually, but aligned with that thing coming true, which makes it significantly more likely to come true.