The Bonus Effect
One Kind of Interest that Rewards Don’t Kill
By Alfie Kohn
For nearly half a century, research has raised troubling questions about the practice of dangling rewards in front of people to get them to do what we want. It doesn’t matter whether the people in question are male or female, children or adults. It doesn’t matter whether the rewards are stickers, food, grades, or money. It doesn’t matter whether the goal is to get them to work harder, learn better, act nicely, or lose weight. What the studies keep telling us is that rewards, like punishments, tend not only to be ineffective — particularly over the long haul — but often to undermine the very thing we’re trying to promote.
Since I reviewed the first wave of research on the counterproductive effects of rewards, new studies have confirmed and extended the original findings. By now, with the exception of economists and a diehard group of orthodox behaviorists (who have restyled themselves “behavior analysts”), most social scientists acknowledge that incentives tend to backfire. Moreover, the problem isn’t limited to particular kinds of incentives or ways of using them. The trouble is inherent to the very idea of incentives. Extrinsic motivators (rewards) tend to reduce intrinsic motivation (people’s interest in, or commitment to, what they’re doing).
Alas, too many parents, teachers, and managers persist in treating people like pets, offering the equivalent of a doggie biscuit to children, students, and employees in an effort to get them to jump through hoops. (Rewards are tools used by people with more power on those with less.) The more familiar you are with the mountain of research on this topic, the more depressed you’ll be to find, for example, that schools continue to rely on Skinnerian programs such as PBIS, Class Dojo, Accelerated Reader, and the like. It’s not just that they’re manipulative, or even that they’re ultimately unsuccessful. It’s that they’re actively harmful.
The early research on rewards investigated some intriguing subsidiary questions that stemmed from the central finding. To wit: What if the reward is really large and luscious? (That tends to compound the damage to intrinsic motivation.) Are rewards damaging mostly because they distract people from the task? (Apparently not, because other distractors don’t have the same negative effects.) What about verbal rewards? (Praise can be just as controlling and destructive as tangible rewards.) Which is worse, giving people a set reward for doing a task or making the reward contingent on how well they do it? (The latter, by a long shot.)
And here’s one of my favorite spin-off questions: If saying “Do this, and you’ll get that” makes people less interested in the “this,” might it also make them more interested in the “that”? The late educational psychologist John Nicholls once quipped that the predictable result of “Book It!” — Pizza Hut’s edible reward-for-reading program — is to produce “a lot of fat kids who don’t like to read.” Too true: Children have been led to see reading not as something desirable in its own right, but as a means to an end, something you have to slog through to get the pepperoni payoff. But might the program also have the effect of enhancing the appeal of pizza just by virtue of framing it as a reward?
This was dubbed the “bonus effect” by a couple of researchers at the University of Colorado who tested the idea in four studies with kids of different ages. They found limited support for the idea that an activity comes to seem more desirable to children who were allowed to engage in it as a reward: It depended on their age and on how familiar they already were with that activity. Two experiments by other researchers — which were focused mostly on whether rewards reduced interest in the target activity — also happened to look at what happened to interest in the reward itself. They found no effect.
Which brings us to what, as far as I know, is the first attempt to revisit this phenomenon in a long time. In a series of seven studies published just this month — exactly 30 years after the same journal featured the Colorado researchers’ findings — two psychologists at Northwestern University’s School of Management used adults as subjects and money as the reward (in six of the seven experiments).
What they found was both straightforward and remarkably consistent: When people are promised a monetary reward for doing a task well, the primary outcome is that they get more excited about money. This happens even when they don’t meet the standard for getting paid. And when a reward other than money is used — raffle tickets for a gift box, in this case — the effect is the same: more enthusiasm about what was used as an incentive.
The researchers also discovered that financial rewards for good performance boosted interest in money more than financial rewards just for participating in the experiment. The more closely a reward is conditioned on how well one has done something, the more that people come to desire the reward and, as earlier research has shown, the more they tend to lose interest in whatever they had to do to get the reward. One of the new studies proved this was true not only in laboratory simulations but also in a real workplace: Monitoring salespeople at a car dealership convinced the researchers that people subjected to performance-based pay “may become more materialistic and less charitable over time.”
Other research has shown that rewards not only reduce people’s interest in what they’re doing but also adversely affect the quality of their performance. When we’re led to focus on getting an A, a bonus, or some other payoff for doing well, we tend to do more poorly on the task — a finding that holds true regardless of age, type of reward, or what we we’re doing (although rewards’ destructive effect on performance is most pronounced for tasks that require creativity or sophisticated problem solving). It’s long been assumed that quality drops because interest drops. But the Northwestern researchers speculated that quality may also suffer from the enhanced interest in, and attention to, the grade or money being dangled in front of people.
The most obvious practical significance of this new research concerns pay-for-performance schemes in the workplace, including bonuses and merit pay. Earlier studies had already shown that compensating people this way makes them less excited about the work they do every day. But it also apparently creates a greater focus on money (compared to other goals and values). And the studies may also be relevant to education. If we try to justify certain instructional approaches by saying they’ll raise test scores, we’re devaluing those approaches while simultaneously elevating the importance of test scores. The same is true of education research that uses test results as the dependent variable.
Also, as I argued not long ago, the same double whammy applies when education itself is justified in economic terms: Students’ engagement declines and their materialistic values — already a dominant feature of our acquisitive culture — may rise. At one stroke we’re teaching them to hate learning and to love money.
The more general conclusion from the new research might be summarized as follows: If the question is “Do rewards motivate people?” the answer is “Sure — they motivate people to get rewards.”
1. I discuss, and provide citations to, all of this research in my book Punished by Rewards (Houghton Mifflin, rev. ed. 1992).
2. Ann K. Boggiano and Deborah S. Main, “Enhancing Children’s Interest in Activities Used as Rewards: The Bonus Effect,” Journal of Personality and Social Psychology 51 (1986): 1116-26.
3. Julia D. Hur and Loran F. Nordgren, “Paying for Performance: Performance Incentives Increase Desire for the Reward Object,” Journal of Personality and Social Psychology 111 (2016): 301-16.