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Does the 'Why' Matter?

A lot of behavioural science focuses on the “why”. Why do we do the things we do? What is our motivation? Or, potentially, what is our lack of motivation? These questions are often the starting point for discovering why a behaviour occurs, especially if that behaviour is not desirable or optimal and requires changing. If you find out why people aren’t getting vaccinated, can you change their mind or circumstance in such a way that they would? Or, potentially less controversial examples: if you find out why people don’t recycle (sustainability), don’t go out to vote (politics), save for a rainy day (economics) or reach out to friends/family in times of need (psychology), can you use that information to change the behaviour? The intuitive answer is: “yes, of course you can”. Models such as COM-B (Capability, Opportunity, Motivation – Behaviour) are centered around this idea that when the “why” has been figured out, we are halfway to a solution.


Now COM-B is both a great model and its own worst enemy; because it sometimes becomes painfully clear from the get-go that some interventions won’t work, when simply applying the model to the situation at hand. For example, you cannot expect a wheelchair user to increase their exercise and reduce their weight through jogging (capability) nor can you expect reduced littering in an area without any trash cans to actually put the litter in (opportunity). But motivation, the “psychological why” is much more difficult. But I’m wondering whether it really matters at all. People’s motivation for reaching a goal is largely based on a belief system. People’s motivation to donate blood is based on the idea that they are helping others, that it is noble to help others, and that it is sometimes even necessary to help others (especially if you’ve got a rare blood type). However, there are also people who don’t donate blood as it is against their religion, or falls outside of the remit of being a good Samaritan. Others are just deadly scared of needles. There’s a plethora of reasons why people may feel strongly about donating blood, either pro or contra. However, the majority of people very often don’t feel strongly about something. They are the rather passive blob in the middle. And it’s in that middle that there’s all to play for. If people don’t have strong opinions about an act, and that act has been deemed desirable (by a government, organization, global leadership etc.), what can you do to make sure the people do what you need them to do?

One answer, as old as time, is to pay people. The motivation for blood donation can be a financial incentive. Why not? Do you honestly care whether the blood that saved your life in a necessary transfusion was “donated” in the purest sense or “bought”? If the option is life or death, I choose life. And I’m pretty sure you would too. However, there are larger concerns on the (operating) table. There are potential drawbacks to paying for this type of “service”, also known as the Titmuss hypothesis. Titmuss argues that paying blood donors would reduce the quality of the donated blood. This reduced quality may occur as the financially vulnerable are especially targeted with this type of financial incentive, with reduced regard for the cleanliness of the blood (disease, drug (ab)use). A 2002 review by van der Poel et al, continues to find that paid blood or plasma donors still have higher rates for infectious disease markers than unpaid donors, confirming the Titmuss hypothesis. A 2013 review by Niza et al, found there was no difference between financial and nonfinancial incentives in the quantity of blood donated. Of the two studies that assessed quality of blood, one found no effect and the other found an adverse effect. They concluded that the limited evidence suggests that Titmuss’ hypothesis of the economic inefficiency of incentives is correct. There is insufficient evidence to assess their likely impact on the quality of the blood provided. So I guess my argument has just been voided. Paying for blood doesn’t seem to be the answer.


Let’s take the argument towards a different, less controversial, sector: recycling. There are multiple countries in Europe (e.g. the Netherlands, Germany) which sell bottles (plastic and glass) as well as plastic crates that hold them (mainly for beer). The shops sells all of these at inflated prices, because there’s a recycling tax on them (in Dutch: statiegeld). This tax is not like the sugar tax: the tax doesn’t exist to discourage usage of the product. No, the tax is refunded, when the product is returned, after consumption. In the Netherlands (amongst other European countries), each shop has a return station for all types of bottles, and the crates as well. The bottle/crate is placed in the machine, the machine scans and identifies the bottle, and after the process is done (I remember many a male frat house returning crate after crate after crate…) the amount to be refunded is printed on a receipt with a bar code. This bar code gets scanned at the till and gets deducted from the shopping total. The money has now been returned. This example is a quick excerpt from a much larger discussion I had as the co-host of the Questioning Behaviour Podcast, interviewing the amazing Melina Palmer. The entire episode is dedicated to the “why” and whether we should actually give a damn about motivation if there’s other, and potentially more effective, ways of getting to the desired behaviour. You can find the podcast here. I think this is a great example of incentivizing recycling through a financial reward. I don’t give a damn why you recycled your 16 beer crates including bottles. The only thing that matters is that they don’t end up polluting the ocean. So I’ll ask you again: does the “why” matter?


Back to more controversial topics: vaccination. There’ve also been discussions about paying people to get vaccinated. Work by Katy Milkman and colleagues has looked at organizing sweepstakes to increase vaccination uptake in the states. And they have worked. Sort of. Milkman et al ran 3 high payoff lotteries in the state of Philadelphia called the Philly Vax Sweepstakes. They had 3 drawings each, 2 weeks apart in June/July 2021. At each drawing 12 prizes were awarded (6 x $1000, 4 x $5000, 2 x $50,000). All Philadelphia adults who were registered on a purchased commercial database were entered into the sweepstake, regardless of whether they had or had not (yet) been vaccinated. It was possible to actively enter which around 6% of the adult population ended up doing. However, only adults who had received at least 1 dose of the vaccine could win the money if their name was pulled in the drawing. 20 ZIP (postal) codes with the lowest per capita vax rates (as of May 2021 – 11 days before the sweepstakes) were included in the experiment. 3 of these ZIP codes were randomly selected to be the treatment group – where the odds of winning the sweepstake were dramatically increased (59 to 98 times higher chance of winning). You’d think that at these odds, people would go bonkers. However, that’s not really what happened. Milkman only saw a slight uptick in vaccinations in the first treatment group immediately following the announcement of the sweepstakes which was not sustained. Neither of the other treatment ZIPS saw an increase. As a result, the cost outweighed the benefit. The lottery produced an estimated 15 extra vaccinations over two weeks at a marginal cost of roughly $62,376 or $4,158 per vaccination, which is an exorbitant price-tag. As much as I love a good pay-out, I wouldn’t recommend anyone to pay that…

Obviously, there are scenarios in which paying for desired behaviour doesn’t work, and actually backfires. There is the famous example of the Israeli daycare, where parents who came late to pick up their children were fined. It wasn’t a big fine either, less than $10, to put in context. However, this backfired (increased lateness, increased fines) as parents now felt that they were “allowed” to come late: they did pay for it after all! Payment can also indicate the privilege to have or do something. There is also the example in Ariely’s and Kreissler’s “Dollars and Sense” that mentions the scenario in which your in-laws cooked you a wonderful Thanksgiving meal (the book is set in the States, I know, let it go). To say thank you, you consider giving them either a gift or money. What is better? Well, you can’t actually pay them for it. It’s not a question of you paying them too much or too little. No, it’s a question of turning an exchange which was based on familial love and effort into a transactional one. The motivation for all the effort put into the meal was not one of finance. However, to balance these things out, often with bigger gatherings and their accompanying meals, there has been a trend towards potlucks – everyone has to bring a dish – to balance out both the financial and time burden. So it’s not as if money has never been a consideration in these scenarios either.


Before this article becomes more like an essay, let’s wrap up. A core aspect of behavioural science is thought of as motivation: the “why”. Why do we do certain things? Once we’ve cracked that code we should be able to start changing behaviour. However, sometimes the “why” is very complex, or based on a belief which would be near impossible to change (beliefs can arise from the most irrational of causes and are surprisingly resistant to facts). Rather than making someone care about the environment (difficult), you can tax and then refund them statiegeld. Suddenly, everyone is bringing back bottles to make sure they’re recycled. The desired behaviour has been achieved. However, things are not always that simple. Financial incentives seem to not have impacted blood donation quantity, and may pose risks to quality (there’s still debate on this). They don’t seem to do much for vaccinations either. Maybe the health domain just isn’t amenable to financial incentivization, who knows? It seems like the social domain isn’t either, so maybe there are things that money just can’t buy. When these financial incentivization schemes do work, and the “why” is money, does that matter? And if so, why does it matter?

1 Comment

Kol Riben
Kol Riben
Nov 28, 2022

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