Main idea

Comparisons between means of payment are ordinarily made on convenience and cost: speed, number of gestures, fees. That frame assumes an environment where paying exposes you to nothing.

In the State of Rio, it does expose you. Visitors are advised against traditional taxis because of the risk of card cloning, and residents recommend Uber, where payment goes through the app. Paying by QR code avoids handing your card to a merchant or a driver. On the seller's side, taking payment by instant transfer avoids keeping the whole day's takings in cash, and therefore becoming a target.

The same gesture then answers a different question: not "which is the most convenient means?" but "which one exposes me least?".

Why it matters

This explains adoptions that an analysis of convenience doesn't predict, and therefore product failures: a faster solution that puts the card back in a third party's hands won't beat a slower one that doesn't require it.

And it makes legible a selling point that appears on no product sheet: non-exposure. It is measured neither in seconds nor in percentage of fees.

Nuances and limits

The risk at issue is perceived as much as observed; perception drives behavior even where the actual frequency is low.

And this motive doesn't replace the others: in the same country, convenience and the cost of collecting payment also drive the choice. It adds to them, it doesn't substitute for them.

Open questions

• How do you build a risk-exposure criterion into a comparison of payment methods, which today is made in fees and delays?