Nudges should help us make better decisions. But a recent study says we can only assess the success of a nudge when we know the nudgees’ true needs. And working these out is difficult because a nudge changes the exact behaviour that demonstrates these needs.
When we make decisions, we often don’t have all the pieces of info we need to puzzle together a rational conclusion. Instead we use mental shortcuts, like a gut feeling, to decide. It works in a similar way to catching a ball without calculating its trajectory.
We tend to dislike losses more than we like gains. So when it comes to incentives, a ‘punishment’ might work better than a ‘reward’. That’s what supermarkets in Washington D.C. found when they tried to reduce the use of disposable bags by taxing them rather than rewarding reusable bag users.