How to Influence Choice Through Default Effect

{ 🧠 } – Choice Architecture and the Cost of Thinking

This article was originally published on UX Planet.

At a school, teen girls had just discovered lipstick. They would go into the toilets to apply it. Then, giggling, they’d leave imprints of their lips on the large mirror. This made a lot of extra work for the cleaning staff. The head teacher asked the girls to stop. Of course, they ignored her. So she took the girls to the toilets for a demonstration. She said, ‘It takes a lot of work to clean the lipstick off the mirror.’ She said to the janitor, ‘Please show the girls how much work it takes.’ The janitor put the mop in the toilet, squeezed off the excess water and washed the mirror. Then put the mop in the toilet again, and repeated the process. From that day on there was no more lipstick on the mirror

—Dave Trott, One Plus One Equals Two

The story is a great example of what is called choice architecture. Don’t try to force people into doing what you want. Accept that they are free to choose. But you can help them to choose what you want and is better for them. If it’s done right.

Choice architecture is the design of different ways in which choices can be presented to consumers, and the impact of that presentation on consumer decision-making. For example, the number of choices presented, the manner in which attributes are described, and the presence of a “default” can all influence consumer choice.

Most of the times we dont realise how important the default setting of a product or service is. It can encourage good or bad habits or it can dramatically increase the revenue of your company. Why is a default setting so influential?

It’s “expensive” for humans to think. It requires a lot of cognitive effort. That’s why we prefer choosing the default or what’s the norm.

That’s why Google is willing to pay billions to other companies for making their search engine default in other browsers. Why? Because almost nobody is going to change it. Defaults can have a significant influence on someone’s behaviour. And they may come in different forms such as written or opt-in/out defaults.

The Default Effect

Related contextual features can influence a person’s actions. For instance, research shows that kitchenware size significantly affects serving and eating behaviour. In a series of studies, people who were given larger bowls served themselves between 28–32% more cereal than those given smaller bowls. Studies also report that people tend to eat 90–97% of what is on their plate, irrespective of plate size.

Experiments and observational studies show that making an option a default increases the likelihood that it is chosen; this is called the default effect.

Different causes for this effect have been discussed. Setting or changing defaults, therefore, has been proposed as an effective way of influencing behaviour. For example, whether you want people to become an organ donor, giving consent to receive e-mail marketing, donate more to your cause, choosing the level of one’s retirement contributions or even a seat on a plane. So our goal is to understand this effect and help our users make better choices.

The job of designers, or choice architects is to remove friction for the user and help it choose the right action.

Would You Share Personal Details by Default?

In a series of experiments, researchers wanted to see how willing people were to share personal details on a “fictional” social media website. People were presented with choices as either opt-in or opt-out. Some were told others not, about what their intent was and how the default effect can influence them. They wanted to examine if knowing about the effect would influence their behaviour.

In one experiment, researches had people decide what information (photographs, location, etc.) they would be willing to share and with whom they would share it (“friends of friends” or advertisers). People were willing to share a third more information when they had to opt-out of sharing than when they had to opt-in. But more importantly, the amount of information they shared did not depend on whether they were explicitly told why the site had set the default the way it did. Even when the site’s goal was to get them to share more info with more people.

Why We Tend to Choose the Default?

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Cognitive effort. If a person’s brain is indifferent or conflicted between options, it may involve too much cognitive effort to make a choice based on researching the product/service. In that case, a person might ignore the any information and choose according to the default heuristic instead.

“If there is a default, do nothing about it” — that’s how our brain thinks about it.

For example, in an experiment, participants were asked to choose between two snacks. They sat in a row and had to wait for their turn to pick. At the same time, they were distracted by a demanding concurrent task (listening to a Podcast or talking to someone). This way, a person was more likely to choose one of two snacks that they saw a previous participant choose. Why? Because it was a default action. They didn’t want to consume more energy in thinking and went with what other people chose.

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The Default Option for Organ Donor

Default opt-in, ranging from deciding whether or not to become an organ donor to making saving allocations for retirement, has been proven to be an effective tool. For example, organ donation rates are 4% in Denmark and 12% in Germany. Why? Because the default option is “opt-in”. Meanwhile, the rates are 86% in Sweden and nearly 100% in Austria where the default option is “opt-out”.

Defaults also might affect the meaning of choice options and thus agents’ choices over them. For example, it has been shown that under an opt-in policy in organ donation choosing not to become an organ donor is perceived as a choice of little moral failing. Under an opt-out policy, in contrast, choosing not to be an organ donor is perceived as morally more deficient. These differences in evaluation might affect the rational choice over these options.

Want People to Donate More to Your Cause?

We put an accent on how objects feel in hand. And even a cheap-feeling paper can lower your donations. Next time when you send that letter in an envelope with your cause and ask for a contribubtion, put the letter in an envelope that’s thicker. This applies both to paper and envelope. Apparently, a thicker paper feels more premium, and you are more comfortable donating a $100 bill than in one that feels cheap.

Boosting Sales with Micro Opt-ins

In an HBR article, Daniel G. Goldstein describes how a large national railroad in Europe made a small change to its website so that seat reservations would be included automatically with ticket purchases. Those tickets come at an additional cost of one or two euros more. The customer, of course, has the option to uncheck this feature.

Before this, only 9% of tickets included reservations. After the change, 47% did. This small change earned the railroad company an extra $40 million annually. Resources spent? Almost none.

Want People to Recycle More?

Don’t tell them, show them. What do you see most companies doing? They try to either ask you to recycle more or say how it’s our fault because of so much plastic. And it’s true, but this is a negative approach. Triggering loss aversion — “look how much we will lose because of that”.

In most cases, people don’t care. Others get angry because you are trying to push them into doing something. But what if you reframed the default message and showed what a plastic could become instead? A default image and copy can dramatically change the way we recycle. Research proves that by showing an “afterlife” for the recycled object, people will be more motivated to recycle. Why is this happening? Because most of us don’t know how exactly recycling works. And we need a way to visualise it and see what’s possible. You can do that by changing the default message and illustration.

Our research suggests that one simple way to increase recycling is to expose consumers to information about the transformation of recyclables into new products, as doing so will inspire them to recycle

— Karen Winterich

People who saw the afterlife of a product were more likely to recycle than those who didn’t. Changing the default message can impact their behaviour. Although triggering loss Aversion can be useful, and saying that “we are all doomed” may improve the number of people recycling, you will still see better results with a positive nudge.

Consider using inspirational nudges over negative ones.

For example, in a test, 111 people were asked to draw on a paper whatever they wanted and then to recycle it. They were given three options, as illustrated in the images above. One group was allowed to recycle in a regular bin. The second group in a container showing how items are recycled into new ones. And the third group was shown the afterlife of those pieces of paper. People who saw the “Afterlife” were more likely to recycle.

We are bombarded daily with news about how the planet is dying, climate change, etc. We know. We all heard about that. So instead of spreading more negativity, try reframing the context and tell a story. Of how an old coke can become a new pair of scissors or other objects you could use.

People know they need to be and do good. Just show them where to go, and behaviour will follow. Instead of saying that plastic harms our planet (which of course it does) you can say that for every 1,000 plastic bottles collected, you can build a playground for kids. People will feel more compelled to contribute and recycle. Also, if you can show them how you did it afterwards, it will increase brand loyalty too. We need more optimism in choice architecture.

Reduce the Default Size to Consume Less

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Want people to consume less? Reduce the default size. Of what? Of anything. Packages, food plates, bottles, etc. For instance, if you would give to one group of people, a big pack of spaghetti, sauce, and meat, they typically will prepare 23% more — around 150 extra calories — than those given medium packages.

In his book Mindless Eating, Brian Wasink found over and over that people eat 20–25% more on average from larger packages or plates. This applies to breakfast, lunch, and dinner foods. For snack foods, it’s even worse.

How Many M&M’s Will You Eat?

In another experiment, Brian Wasink and his team asked 40 adults at a meeting to watch a videotape and provide some feedback about it. As a thank you, they were each given a bag of M&M’s — either a 250g or a 500g bag — to enjoy while they watched the tape. The researchers didn’t care what they thought about the tape, they only cared how many M&M’s they would eat while watching it.

The results were dramatic. Those who were given a 250g bag ate an average of 71 M&M’s. Those who were given the 500g bag ate an average of 137 M&M’s, almost twice as many (around 264 extra calories). Sure, a person saves some money by buying the big bag, but if he decides to do some binge watching, it will also cost him some extra weight.

We all consume more from big packages, whatever the product. Give people a large bag of dog food, they pour more. Give them a large bottle of liquid plant food, they pour more. Give them a large shampoo bottle or container of laundry detergent, they pour more. With the 47 products we’ve examined, the bigger the package, the more they use

— Brian Wansink, Mindless Eating

How Disney Did It

Walt Disney World, for example, changed the default choices in its kids’ meals — swapping soda for juice and fries for fruits and vegetables — leading to the consumption of 21 percent fewer calories, 44 percent less fat and 43 percent less sodium. And Vanguard reported that automatically enrolling new employees in a retirement plan more than doubled participation rates.

How to Apply This Type of Behaviour?

Take as an example fromGoogle that redesigned their cafeterias to encourage healthier eating habits. When you are hungry, you tend to grab the first thing you see. Now, the most nutritious options are positioned at the front of the cafeteria. Meanwhile, the unhealthy foods are hidden in the back. They made the smaller plates a norm and marked with reminder messages that “bigger dishes prompt people to eat more.” Foods are tagged with either red “warning” stickers, or green stickers signifying healthy foods.

Beverage coolers have water at eye level, and sodas are at the bottom where they can’t be easily seen or accessed. These changes — which notably do not restrict options, but rearrange the way options are presented — have led to reductions in candy and sugar-sweetened beverage consumption, and increases in the use of smaller plates.

What About Other Cases?

Let’s say you have an app that sells food. Put the low calorie food first and the others last, so it’s harder to find. Maybe you have a fitness app which tracks calories? Increase the default calorie necessary per day by 50 or 100. Or your app tracks analytics and sends email marketing? Uncheck the box for the user, so they don’t receive it, this way increasing trust towards your brand. Want to get more donations? Increase the default number of how much they can donate. For example from $2 to $5.

The Defaults Are Here to Stay

The power of default is clear, and the range of possiblities is big. Less cognitive effort can help your users make better decisions. You have the power and you choose how to use it.

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Eugen Eşanu Avatar

Eugen Eşanu / Founder @

Designer and casual writer. Currently building