You are standing in your own store. The range has been refreshed, the product pages look beautiful, the reviews are positive, the prices are sharp. And yet: 70% of online shopping carts are abandoned before checkout.[1] In the physical store, you pull up the customer data and discover they say one thing in the satisfaction survey and do something entirely different at the till.
At SUE, we see this pattern with every retailer we work with. It is not a marketing problem. It is not a UX problem. It is a behaviour problem. And the core is always the same: retailers optimise for what customers say they want, while purchase behaviour is driven by forces customers themselves cannot name.
Clayton Christensen called this the difference between what a customer buys and what a customer “hires” the product to do.[3] A fast-food chain sold more milkshakes when they discovered that customers weren’t buying the milkshake as a dessert but as a companion for a long, boring commute to work. The milkshake had a job: make the drive bearable. Only when they made the milkshake thicker, so it lasted longer, did sales rise. Not by improving the flavour. By doing the job better.
That is precisely what behavioural design does in retail.
Behavioural design for retail applies behavioural science to the gap between customer intent and purchase behaviour. It starts with the Job-to-be-Done: the underlying problem the customer is trying to solve. Using the SUE | Influence Framework©, you map the psychological forces that drive and block the purchase. With the SWAC Tool©, you design interventions at the exact moment where the decision happens. You change the environment, not the customer.
The numbers behind the behaviour gap
Why retail needs behavioural design
Retail operates on an assumption that drives an enormous amount of wasted investment: that customers who say they are interested will behave as though they are interested. This is what we at SUE call the stated preference trap. Ask a customer whether they would buy a sustainable product if it were the same price and quality, and 80% say yes. Put that product on the shelf next to the familiar brand, and the familiar brand outsells it four to one.
Daniel Kahneman explained why.[6] Our brain operates in two systems. System 2 is the conscious, rational mind: comparing specifications, reading reviews, weighing prices. System 1 is the fast, automatic system: reaching for what you always buy, following the “most popular” badge, abandoning the page when there are too many options. Around 95% of our daily decisions are made by System 1.[6] And virtually every purchase decision in a supermarket, a fashion store, or an online shop is a System 1 decision.
That means the customer standing in the Tesco aisle at 6pm on a Thursday is not performing a cost-benefit analysis. She reaches for what she bought last week. Not because she decided it was the best option, but because her brain made the decision before she reached the shelf. The customer browsing Amazon at 11pm is not carefully evaluating every specification. He is being nudged by scarcity signals, anchored by the recommendation badge, and held back by the fear of choosing wrong.
You don’t change behaviour by working at the behaviour itself. You change the environment in which the behaviour takes place.
This is the core principle of behavioural design, and it captures the essence of what retail can learn from behavioural science. As Tom and I write in The Art of Designing Behaviour: “Simplicity eats willpower for breakfast.”[13] Your customers do not need to be smarter, better informed, or more motivated. The choice environment needs to be designed so the desired behaviour is the easiest behaviour.
But before you can redesign the environment, you need to ask the right question. Not: “how do we sell more?” But: “what job is the customer trying to get done, and what is blocking that job at the moment of decision?”
Three retail challenges that behavioural design solves
Challenge 1: the loyalty programme that rewards but doesn’t retain
At SUE, we worked with a fashion retailer that seemed to be doing everything right. A generous points system, double points in sale periods, tier upgrades with real benefits. Customer satisfaction with the programme was high. The redemption rate after eighteen months: 11%. The marketing team responded with more communication: email reminders about accumulated points, push notifications about expiring rewards, a redesigned app.
Engagement ticked up briefly after each campaign. Then it fell back to baseline.
Because communication was not the problem. The programme was built on the assumption that customers are rational decision-makers who systematically track and optimise rewards. That customer does not exist. Points are abstract. Redemption requires deliberate effort. The reward is deferred. And the act of using your points feels like administrative work, not receiving a gift. Research by Nunes and Dreze on the endowed progress effect revealed something remarkable: a loyalty card requiring ten stamps but with two already stamped was completed at significantly higher rates than a card with eight empty stamps, even though the required effort was identical.[7] Not the size of the reward, but the feeling of progress determines whether someone continues.
Challenge 2: the product page that informs but doesn’t convert
You are the product manager at an online electronics retailer. The product pages are beautiful: every specification listed, comparison tables, 400 customer reviews, five high-resolution images, a video demo. The conversion rate is 1.8%. Industry average for electronics is 2.3%. Your hypothesis: customers need more information. You add a live chat function, an AI product advisor, and an expanded FAQ section.
Conversion drops to 1.6%.
The problem is not a deficit of information. It is a surplus. Sheena Iyengar and Mark Lepper demonstrated this in their famous jam experiment: a display with 24 jams attracted more visitors, but a display with 6 jams sold ten times more.[4] Barry Schwartz called this the Paradox of Choice: above a threshold of options, the brain shifts from choosing to deferring.[8] A German car manufacturer tested this with their online configurator: customers who started with easy choices (colour) and finished with hard ones (engine) completed the process. Customers who started with hard choices abandoned or accepted all defaults. Same options, same information, different order.
Amazon understood this earlier than anyone. When they replaced the “Register” button at checkout with “Continue” and the message “You do not need to create an account,” revenue rose by $300 million in the first year.[5] They added nothing. They removed one friction threshold.
Challenge 3: the sustainable range that sits on the shelf
You launch a premium sustainable product line across twelve categories. Well-sourced, clearly labelled, priced at 15% above the conventional equivalent. Consumer research says 74% of your target segment values sustainability and would pay more for it. After six months: 6% market share. Your customers genuinely value sustainability. But at the shelf, at 6pm on a Thursday, they reach for the familiar product.
This is the intention-action gap in its purest form. The customer who values sustainability uses System 2. The customer doing the weekly shop on a Thursday evening uses System 1. And System 1 defaults to habit.
The solution is not better communication about sustainability. The solution is changing the default. Johnson and Goldstein showed this with organ donation: in countries where donation is the default, registration is nearly 100%. In countries where you have to actively opt in: 20-27%. Not a cultural difference, a default difference. Home Retail Group applied the same principle to their donation programme: by changing payroll donation from opt-in to opt-out, participation rose from 10% to 49%.
Influence Framework analysis: what drives and blocks purchase behaviour
Every purchase decision begins with a Job-to-be-Done.[3] A customer does not buy a drill, she wants a hole in the wall. A customer does not buy a jacket, she wants to feel protected in bad weather, or she wants to look good on a first date. The SUE | Influence Framework© then maps the four forces that determine whether the customer actually fulfils that job by buying your product, or whether she defers, sticks with the familiar brand, or simply does nothing.
Why customers browse, add to cart, and still don’t buy
In retail, the driving forces are well addressed: customers know what you sell, they understand the value proposition, they are attracted to the product. What stops them is not a lack of desire. It is a combination of blocking forces that operate at the moment of decision, below the level of System 2 deliberation. I have seen this in dozens of retail projects at SUE: the real conversion work happens at the blocking forces.
Dissatisfaction with the current situation: customers who are browsing are already experiencing some dissatisfaction. A broken appliance, a wardrobe that feels stale, a previous brand that disappointed. This is a genuine driver and the reason they are on your site or in your store at all. But dissatisfaction alone does not convert. It creates openness, not action.
Time pressure: the urgency of needing something now is one of the strongest drivers of purchase completion. A gift for tomorrow, a replacement for something that just broke, a solution to an immediate problem. Scarcity signals and limited-time offers create artificial urgency for customers browsing without natural time pressure.
Social trigger: seeing someone else with a product, a recommendation from a friend, a season change. North, Hargreaves, and McKendrick found that when French music played in a wine shop, French wine outsold German wine five to one, and vice versa.[8b] Customers denied afterwards that the music had influenced them. Social triggers are powerful, episodic, and operate entirely below awareness.
Identity expression: shopping is not purely functional. Products signal who you are. Apple sells not just devices but belonging to a certain kind of person. Patagonia customers are not just buying a jacket but affiliating with a set of values. The emotional gain of a purchase is often stronger than the functional one.
Value perception: customers want to feel they got a good deal, even when they are not price-sensitive. The perception of value is relative. That is why anchoring is so powerful: show the original price next to the sale price, and the sale feels like a win, regardless of what the original price actually was.
Job fulfilled: for functional purchases, the anticipated relief of having the problem resolved is the real gain. That is why good product pages emphasise outcomes, not features. You are not selling a drill, you are selling the hole in the wall.
The comfort of the familiar brand: habit is the most powerful force in retail and it almost never shows up in customer research. People do not experience their habits as decisions. They simply reach for what they always buy. Research shows it takes an average of 66 days to form a new habit.[10] That means as a retailer you do not need to win one purchase, but a series of purchases over two months. The familiar brand is not chosen. It is defaulted to.
Existing routines: customers shop in patterns. They visit the same sections, follow the same route, buy from the same three brands per category. These routines are comfortable precisely because they require no mental effort. Introducing a new product requires a deliberate intervention at the moment the routine would otherwise play out automatically.
Satisficing: most customers are not optimising. They are looking for something good enough. When the current product is good enough, the energy required to switch is higher than the perceived benefit of the alternative. “Good enough” is where most customers live. It is stable.
Fear of choosing wrong: the anxiety of post-purchase regret is one of the most powerful barriers, particularly for higher-value purchases. A customer who buys the wrong laptop experiences real negative consequences: wasted money, the effort of returning it, the feeling of having been foolish. More options amplify this anxiety: Schwartz called it the Paradox of Choice.[9] The more alternatives, the greater the chance of regretting not choosing the other one.
Price anxiety: even when a customer wants a product and can afford it, the question “am I paying too much?” can block the purchase. This is especially acute in categories where online price comparison is easy. Coolblue’s price-match guarantee is not a pricing measure. It is an anxiety-reduction intervention.
Delivery and returns uncertainty: online purchase anxiety concentrates around two questions: “will this actually arrive?” and “what if it is not right?” Coolblue built an entire brand around eliminating precisely these two anxieties. Zappos did the same with free returns. The return policy is not just operationally generous. It is a behavioural intervention that removes the biggest blocker to online purchase completion.
The key insight: retail marketing overwhelmingly targets the driving forces: create desire, communicate value, build awareness. But whether someone buys or walks away is determined by the blocking forces. They operate at the moment of decision, below the level of conscious deliberation. The comfort of the familiar brand and the fear of choosing wrong are not overcome by a better ad campaign. They are overcome by redesigning the choice environment so the desired behaviour is easier, less risky, and more immediately rewarding than the default of doing nothing. As Tom and I write in The Art of Designing Behaviour: influence is far more judo than karate.[13] You use the existing forces, you do not fight them.
Five behavioural interventions for retail
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Reduce choice architecture friction at point of purchase (CAN: C01, C02, C07)
More options do not increase purchase likelihood. The jam experiment is now a classic in behavioural science: 6 options sold ten times more than 24 options, even though 24 attracted more browsers.[4] Redesign category pages to lead with a clear recommended option (C01: default). Use editorial curation: “Best for most people,” “Best if you need X,” “Best budget choice.” This does not limit the customer. It does the mental work that overwhelmed customers would otherwise defer. Define one next step (C07: dominance): not three buttons, but one action that feels logical.
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Use scarcity and social proof to trigger action (SPARK + WANT)
Customers in a browsing state need something to shift them from consideration to commitment. Scarcity (“only 3 left in stock”) creates urgency by making inaction feel like loss. Social proof (“248 people bought this today”) reduces the fear of choosing wrong by providing social validation. Goldstein, Cialdini, and Griskevicius showed that in hotels, a simple social norm (“most guests reuse their towel”) was significantly more effective than an environmental message. The combination of scarcity and social proof at the product decision moment is consistently the highest-converting intervention in e-commerce. Not because these are tricks, but because they provide information that makes the decision easier.
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Design the default towards desired behaviour (CAN: C01)
The most powerful intervention in behavioural design is almost always the simplest: change the default. With organ donation, the difference between opt-in and opt-out is the difference between 20% and nearly 100% registration. In retail, the same principle applies to every product category, from sustainable options to subscription models. Position the desired product as the standard and make the alternative available for those who actively seek it. This is not manipulation. It is alignment between what customers say they want and what the choice environment makes easy for them to do.
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Design the post-purchase experience to build habit (AGAIN: C13, C18)
The moment immediately after a purchase is the highest-value moment in the customer relationship, and most retailers waste it with a transactional order confirmation. Research by Lally showed that new habits take an average of 66 days to become automatic.[10] IKEA understood this instinctively: Tom and I analysed their in-store experience and found an enormous dip in customer satisfaction between trying products in the showroom and the self-service warehouse pickup.[13] The cheap hotdog and ice cream at the exit compensate for that dip via the peak-end effect.[11] You remember the best moment and the last moment. IKEA designs that last moment deliberately. Redesign the post-purchase moment as a habit-building intervention (C18: schedule). Give the customer a head start towards the next purchase (C13: endowed progress). Design the re-engagement sequence to feel like a natural next step, not marketing.
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Frame pricing to reduce loss aversion (WANT)
Loss aversion means the pain of losing money is roughly twice as strong as the pleasure of gaining equivalent value.[6] Pricing communication framed around what you are saving (“save €40”) outperforms communication framed around what you are spending. Subscription pricing framed as “less than a coffee a day” outperforms equivalent monthly sums. The decoy effect, introducing a third less-attractive option to make the target option look better, is one of the most consistently replicated findings in behavioural economics.[12] The Economist used precisely this: a print subscription for $125 became irrelevant once the combined print+digital subscription was also $125. The print option existed not to be sold. It existed to make the combined option feel like the obvious choice.
Which cognitive biases matter most in retail
Retail decisions are shaped by the same cognitive biases that operate everywhere in life, but the density of those decisions (dozens per shopping trip, hundreds per week) makes them especially suited to behavioural intervention. These are the five biases with the greatest impact on purchase behaviour.
Anchoring bias
The first price a customer sees becomes the reference point. Show the original price before the sale price, and the discount feels larger than it is. Ariely, Loewenstein, and Prelec showed that even a random number (the last two digits of your social security number) influences the price people are willing to pay for a product. IKEA and Amazon use anchoring as a structural element of their entire pricing architecture.
Read the full analysis → Behavioural DesignDecoy effect
A third, strategically inferior option makes the target option look more attractive. Retailers use this with three product tiers, three subscription levels, or three pack sizes. The small size exists to make the medium feel like a deal. The Economist made this world-famous with their subscription options.
Read the full analysis → Behavioural DesignScarcity principle
Products that appear limited in availability are perceived as more desirable. “Only 2 left in stock” shifts a browsing customer into urgency mode. Limited editions, flash sales, and exclusive early access for members all use scarcity to convert browsers. In 1983, Cabbage Patch Kids caused literal riots in department stores through artificial scarcity.
Read the full analysis → Behavioural DesignSocial proof
When customers are uncertain, they look at what others are doing. Review counts, bestseller badges, and “most popular in your area” signals reduce choice anxiety by providing a social shortcut. Goldstein and Cialdini showed that hotel guests reused their towel significantly more often when told that most guests in their room did the same.
Read the full analysis → Behavioural DesignLoss aversion
Customers are more motivated by avoiding loss than by achieving a gain. “You’re missing out on €40” outperforms “save €40.” Loyalty points that expire create more engagement than points that accumulate. Return policies that eliminate the risk of loss remove the biggest barrier to first-time purchase.
Read the full analysis →Frequently asked questions
How does behavioural design apply to retail?
Behavioural design for retail starts with the customer’s Job-to-be-Done: not what product they are buying, but what problem they are solving. Using the SUE | Influence Framework©, you map the four forces that drive and block purchase behaviour: Pains, Gains, Comforts, and Anxieties. Then you design interventions with the SWAC Tool© at the exact moment where the purchase decision happens. You change the environment, not the customer.
Can behavioural design reduce cart abandonment?
Yes. Cart abandonment is a behavioural problem, not a product problem. Customers add items fully intending to buy. They do not complete the purchase because of friction (too many checkout steps), anxiety (uncertainty about delivery or price), and present bias (the purchase feels less urgent once they leave the product page). Amazon calculated that removing one friction threshold was worth $300 million in its first year.[5]
What is the difference between CX and behavioural design?
Customer experience (CX) measures satisfaction and stated preferences: how happy were you? Behavioural design asks a different question: what actually determines whether someone buys, returns, and stays loyal? CX optimises for what customers say they want. Behavioural design optimises for how customers actually behave. A customer can rate their experience 9 out of 10 and never return. The gap between those two is precisely the territory of behavioural design.
Why do loyalty programmes fail to build loyalty?
Most loyalty programmes are built on a rational model: accumulate points, redeem, stay loyal. But loyalty is not a rational calculation, it is a habit. Habits take an average of 66 days to form.[10] Point systems fail because the reward is deferred and abstract. Behavioural design redesigns loyalty around immediate reinforcement and habit formation. The question is not “how do we make the points more valuable?” but “how do we make the next purchase automatic?”
What is a Job-to-be-Done in retail?
A Job-to-be-Done (JTBD) is the underlying problem a customer is trying to solve by “hiring” a product.[3] Clayton Christensen discovered that a fast-food chain sold more milkshakes by understanding that customers hired the milkshake as a companion for a boring commute, not as a dessert. In retail, JTBD means you stop optimising for product features and start designing for the moment and the problem that triggers the purchase.
PS
I have spent years working with retailers who are genuinely talented at their craft. Beautiful stores, excellent product selection, carefully designed customer journeys. And yet that gap persists: between what customers say and what they do, between purchase intent and purchase behaviour, between the product page and the checkout. The 70% abandonment figure is not a sign of bad design. It is a sign of design that optimises for the wrong system. System 2 is served by information, arguments, and features. System 1 is served by defaults, friction, and social signals. Once you understand that distinction, everything changes. Not the product needs to be different. The choice environment does. That is the core of what Tom and I describe in The Art of Designing Behaviour, and what we do every day at SUE. Your customers want to buy from you. Design an environment that makes it easy.
