Because if human beings were entirely rational, nobody would own a kitchen gadget they’ve used once.
Marketing has traditionally been rather fond of the idea of the rational customer.
This imaginary customer figures out what they need, looks at all the options, compares features and prices, thinks about the value, and then calmly picks the best product.
They are magnificent.
They also seem extremely rare.
Real customers are human beings.
They get distracted, put things off, follow what others do, worry about making mistakes, stick with brands they know, are swayed by how choices look, and sometimes buy something just because the packaging is appealing.
This isn’t necessarily stupidity.
It’s simply how human decision-making works.
And understanding it is where behavioural science becomes enormously useful to marketers.
We Like to Think We’re Rational
Ask someone why they bought a particular car, laptop, pair of shoes or piece of business software, and they’ll usually provide a perfectly sensible explanation.
It had the right features.
The price was competitive.
The specifications were better.
It integrated with the existing system.
All thoroughly rational.
But decisions are also influenced by emotion, familiarity, previous experiences, perceived risk, context and what other people are doing.
Behavioural economics started by questioning whether people always act in perfectly rational ways. Studies on consumer behaviour have shown that shortcuts, emotions, social influences, and the way choices are shown all play a role.
In other words, customers don’t arrive at decisions carrying tiny spreadsheets inside their heads. Which is disappointing for spreadsheets.
Our Brains Like Shortcuts
Making decisions takes effort. Imagine carefully analysing every decision you make during a normal day.
- Which coffee?
- Which route to work?
- Which email first?
- Which toothpaste?
- Which supplier?
- Which sandwich?
By lunchtime you’d be lying beneath your desk whispering: “I simply cannot evaluate another yoghurt.”
So our brains use shortcuts.
Behavioural scientists call these shortcuts heuristics. These are mental rules that help us make decisions without having to think through every single option.
Usually, they’re incredibly useful.
Sometimes, these shortcuts mean we go into IKEA for a lamp and leave with a lamp, twelve tealights, two storage boxes, and something called a KALLRÖMP, which we think might be a stool or maybe a salad bowl.
For marketers, the important point is that customers don’t evaluate everything equally.
Certain pieces of information carry disproportionate weight.
The First Number Can Change Everything
Consider pricing.
Imagine you’re looking at three versions of a product:
- £29
- £59
- £149
Suddenly £59 can feel quite reasonable.
Remove the £149 option and £59 may start looking expensive.
The product hasn’t changed.
The context has.
This is connected to anchoring and reference points. The choices around a decision can change how customers see value, and adding an extreme option can make other choices look more appealing.
This is why pricing pages so often contain several tiers.
It’s not simply about offering different products.
The options help customers understand what the other options mean.
£100 in isolation is just £100.
Next to £300, it can suddenly look reassuringly economical.
Money works in strange ways.
Other People Are Extremely Persuasive
Humans are social creatures.
When we’re uncertain, we often look at what other people are doing.
This helps explain the power of reviews, testimonials, recommendations, case studies, customer numbers and phrases such as: “Most popular.”
If thousands of other people have bought something, we instinctively suspect they might know something.
This is generally useful.
If you walk past two restaurants and one is bustling while the other contains a single server staring sadly through the window, you may draw certain conclusions.
This is social proof.
Studies on choice architecture show that social norms and information about what’s popular can strongly influence behaviour, especially when people are unsure about what to pick.
That’s why a genuine customer saying: “We used this and it solved our problem.” can sometimes be more persuasive than a company saying: “We provide market-leading innovative solutions.”
Particularly because approximately 97% of companies appear to provide market-leading innovative solutions.
We Don’t Particularly Like Losing Things
Another famous behavioural idea is loss aversion.
Broadly, the idea is that potential losses can affect decisions differently from equivalent gains.
There is evidence that loss aversion affects product choices, but research also shows it is stronger in some situations than others. It’s not a one-size-fits-all solution.
That distinction matters.
Behavioural science is useful.
Behavioural science isn’t very helpful if it’s just summed up in a LinkedIn graphic that says “HUMANS HATE LOSING TWICE AS MUCH AS THEY LOVE WINNING.”
Still, risk matters enormously in marketing.
Customers aren’t only asking: “What will I gain if I buy this?”
They’re also wondering:
- What happens if I get this wrong?
- Will I waste money?
- Will implementation be difficult?
- Will my boss think I’ve made a terrible decision?
- Will switching suppliers create problems?
- Will I spend the next six months in meetings explaining why the new CRM doesn’t work?
Reducing perceived risk can therefore be just as important as increasing perceived benefit.
Testimonials, guarantees, trials, demonstrations, clear onboarding and credible case studies can all help.
Not because customers are irrational.
Because they’re trying to avoid regret.
More Choice Isn’t Always Better
Businesses frequently assume customers want more options.
So they provide them.
- Basic.
- Standard.
- Professional.
- Professional Plus.
- Premium.
- Premium Plus.
- Enterprise.
- Enterprise Advanced.
- Enterprise Advanced Pro.
And something called Ultimate, which presumably includes access to the company helicopter.
The customer looks at all of this and decides to think about it later.
Research into choice overload suggests that larger assortments can sometimes make decisions harder, particularly when the choice itself is complicated, preferences are uncertain, or the decision requires significant effort.
This doesn’t mean customers always want fewer choices.
It means more isn’t automatically better.
Sometimes, good marketing means helping customers make a choice instead of just adding even more options for them to consider.
Familiarity Is Remarkably Powerful
There’s also comfort in what we already know.
People often return to familiar brands, suppliers and products even when alternatives exist.
Partly because switching requires effort.
Partly because the familiar option feels less risky.
And partly because nobody wants to spend Thursday afternoon comparing broadband providers.
This is why brand building matters.
Seeing a brand often, having consistent experiences, using familiar visuals, and having a clear reputation all help reduce uncertainty.
Eventually your brand moves from: “Who are they?” to: “I’ve heard of them.” to: “They seem credible.” to: “Let’s talk to them.”
No single advert necessarily caused the decision.
Trust accumulated.
Emotion Isn’t the Opposite of Logic
Marketers sometimes act like rational and emotional decisions are totally separate, as if customers switch between two different modes.
BUSINESS MODE: LOGICAL.
CONSUMER MODE: PURCHASES NOVELTY WAFFLE MAKER.
Reality is more complicated.
Even supposedly rational B2B decisions involve confidence, fear, reputation, familiarity and perceived personal risk.
Imagine choosing between two suppliers.
Both offer similar capabilities.
One responds quickly, explains things clearly, has credible case studies and makes the process feel straightforward.
The other sends a 63-page proposal filled with phrases like “leveraging synergistic transformational ecosystems.”
Which feels safer?
That feeling matters.
Behavioural Science Isn’t About Tricking People
This is where marketers need to be careful.
Once you understand behavioural principles, it’s tempting to treat them as a box of psychological buttons.
PRESS HERE FOR URGENCY.
PRESS HERE FOR SOCIAL PROOF.
PRESS HERE TO MAKE CUSTOMER BUY THING.
That isn’t behavioural science.
That’s just manipulation in disguise.
Choice architecture can help people make decisions, but regulators and researchers also recognise that the same techniques can harm consumers when used deceptively, for example, through misleading scarcity, defaults, or pressure tactics.
Fake countdown timers.
Invented scarcity.
Hidden subscriptions.
Pre-ticked boxes.
Deliberately confusing cancellation processes.
These may produce short-term conversions.
They can also produce angry customers, regulatory attention and reviews that begin with: “AVOID.”
Good behavioural marketing should make decisions easier, clearer and more relevant.
Not trick people into making decisions they wouldn’t otherwise make.
Start With Behaviour, Not Biases
The biggest mistake marketers make with behavioural science is beginning with a list of biases.
Anchoring!
Scarcity!
Social proof!
Loss aversion!
Quick, put them on the landing page.
A better starting point is the customer.
- What are they trying to achieve?
- What is stopping them?
- What are they worried about?
- Where are they confused?
- What information do they need?
- Who influences their decision?
- What feels risky?
- What makes one option easier to understand than another?
Then behavioural science can help explain what’s happening.
The objective isn’t to make customers irrational. They were already human when they arrived.
The objective is to understand how real people make decisions and design marketing that works with that reality.
Marketing Is Ultimately About People
Technology will continue changing marketing.
AI will become more capable.
Analytics will become more sophisticated.
Personalisation will become more precise.
We’ll probably end up with dashboards that track things we never even thought needed tracking. But underneath all that technology sits the same gloriously inconsistent creature we’ve been trying to understand for decades.
A human being.
Someone who uses logic but also emotion.
Someone influenced by other people.
Someone who dislikes uncertainty.
Someone who notices context.
Someone who takes mental shortcuts.
Someone who might spend six weeks researching a £30,000 business purchase and then choose the supplier because: “They just seemed to understand us.”
That’s why behavioural science matters.
Because good marketing isn’t simply about understanding what customers should do.
It’s about understanding what people actually do.
And, more importantly:
why.
