Fear

Fear narrows attention onto the immediate threat. This is a physiological response rather than a lapse in judgement: the stress response prioritises fast action over careful evaluation, and reduces the capacity to absorb new or contradictory information. Victims frequently describe being "in a haze" or "on autopilot", which is an accurate description of what is happening.

Scam scripts built on fear rarely stay there. They oscillate. A threat is introduced, then a solution is offered, and the relief of the escape is itself part of the mechanism, because complying is rewarded with the removal of the fear.

This is why warnings often fail to land at the moment they are most needed. A bank employee or a family member raising a concern is asking a frightened person to perform exactly the deliberation the fear has suppressed. Good scripts also anticipate that moment and pre-arm the victim against it.

The countermeasure is procedural rather than analytical. Not "assess whether the threat is real", which is what fear prevents, but "end the contact and verify on a channel you initiated". That works while frightened.