Usually what happens is that you get a customer team, that is supposed to voice how the organization wants the software to be.

So the same mismatch is bound to happen anyway.

And when they do involve the people from the field, depending on the company culture, they might even be quite positive on the demos (cause being negative isn't good) and then completely find it unusable on final delivery.

Agile misses that many engineering teams lack people skills to actually navigate and avoid these scenarios.

EDIT: several typos