Why do smart, careful people fall for scams?

Smart, careful people fall for scams because a scam is not a test of intelligence. It is an attempt to defraud someone after first gaining their trust, and it works on ordinary human tendencies such as credulity, compassion, vanity and greed. Researchers who study cons say there is no consistent profile of a victim. The one thing victims share is that, at the key moment, they relied on the good faith of the person in front of them.

Scammers also use pressure points that psychologists have measured in everyday life. One is authority: in one study, passers-by were twice as likely to obey a stranger in a security guard's uniform as one dressed as a milkman. Another is reciprocity, the feeling of owing someone something, which can appear even after a favour nobody asked for. A third is urgency: con artists call it the "hurrah", a sudden manufactured crisis that forces you to act now, before you have time to think or ask anyone.

Then there is the pull of what you have already put in. Once a victim has paid in time, money or hope, stopping feels like admitting the loss, so people caught in scams often keep going despite doubts. This is called the sunk cost fallacy. It is also why many victims are slow to believe the truth, and why the stigma of having been fooled stops many from reporting the crime at all.

The word "con" itself has a funny origin: the first "confidence man" was a clumsy swindler who simply asked strangers to hand over their watches as a sign of trust.