Deal or dud?: The psychology of shopping the sales

From bulk buying products you only needed one of, to ending up with a Christmas outfit for your cat and beard baubles for your mate, we're probably all guilty of getting a bit over-enthused about the Black Friday sales.

But it's not just price cuts that companies use to draw us in. Find out what other tricks retailers use to get us to part with our cash...

1. The limited time offer

"Black Friday is a classic example of this," says consumer behaviour expert Richard Maule. "We’re more inclined to purchase something if we think it will be gone tomorrow." Psychologists call this the ‘scarcity principle’. A classic 1975 study found that when people were given a jar of ten biscuits and a jar of two biscuits, those who had the emptier jar rated the biscuits as more valuable. So if you think that’s the last pair of boots in your size, or they’re 30% off today only, that might be why you want them so much.

2. The one-stop shop

Jessica, 27, from London felt like she’d got a great deal on a new mop, only to discover it was doll-sized when it arrived! As Richard explains: "People buy with emotions not with logic." So the company will make the buying experience as easy, quick, simple and therefore as enjoyable as possible. Think of online one-click checkout or contactless credit card taps. They will also sell the ‘what’ of the product or service as a secondary thing so that the buyer can justify their emotional decision. They only think of the 'why' later.

3. Psychological mind games

If you leave the supermarket with a bulging trolley when you only popped in for milk – here’s why. "Many shops especially supermarkets, will move products around so that you are forced to scan the shelves and see more things you want to buy," says consumer branding expert Martin Lindstrom.

"They also move dairy products to the middle of the store," he says. "Another common feature is a one-way entry door, so you have to move around the whole store to get out. The most expensive items are often placed at eye-level and the displays at the end of aisles – known as ‘end caps’ are designed to grab attention and attract impulse buyers."

4. No such thing as free shipping...

Free postage when you buy online might sound like it’s saving you money, but beware the sneaky threshold if it’s only over a certain amount. "Stores know that our brains would rather purchase more than pay for shipping," says Martin. "So this is another way to encourage overspending."

5. Or a free sausage...

If you’re in a supermarket and you sample some free food, you know you’re under no obligation to buy it, but your brain does something else. Psychologist Robert Cialdini calls it the 'rule for reciprocation': if someone does something nice for you, you're more inclined to do something nice for them. It also tells your body it’s dinner time, which tunes your brain into the topic of food, even if you only wanted to buy toothpaste.

6. Shop while you bop

Music encourages us to dawdle and spend more – an effect that has been known about for years. A study of background music and supermarket shoppers from 1982 found that people spent 34% more time shopping, with a corresponding uptick in sales, in stores that played music. Slow music makes people shop leisurely and spend more. Loud music hurries them through the store and doesn't affect sales. Classical music encourages more expensive purchases. Supermarkets also tend to be devoid of external time cues: most have no windows or skylights, and shoppers are often hard-pressed to find a clock.

7. There’s an app for that

"Shops encourage you to download their app by offering you a discount if you do," says Richard. "This is to make shopping more seamless but also to put you in the mood for shopping with flashing notifications and alerts about their latest sale items. And there’s a reason alerts are often red – people react more forcefully to this colour."

8. Save a penny?

"Pricing a product at 99p causes consumers to automatically round down," says Martin. "Likewise if a product costs £39.99 we think of it as costing more like £30 not £40."

9. Beware ‘vani-sizing’

Tempted to buy those jeans because they’re a size smaller than you normally wear? That could simply be ‘vani-sizing' – when shops make clothes bigger so we think we can fit into a smaller size, and it’s "in nearly every store out there," according to Martin Lindstrom. "Our purchase decisions are one part logic and at least one part emotion. Advertisers play on feelings like size envy to motivate us to buy."

And if you thought the changing room was really flattering, you weren’t just having a good hair day. "Playing with light is a huge one," says Lindstrom. "Many stores add a slight rosy tint to the lights to make us look healthier when we try on clothes."

10. The rule of FOMO

"Nothing attracts a crowd like a crowd and the fear of missing out," says Richard. "This is why online stores will tell you ‘three people currently have this item in their basket’ or ‘five people recently booked this holiday,’" he says. "If the company can show that lots of people are buying the product or service then others follow. A perfect example is when there is a crowd gathering in the street or a queue, the first instinctive reaction is to wonder, ‘what interesting thing is happening there? I better go and have a look!’ Before you know it, you’re at the checkout."

So there you have it – those retailers are a smart bunch. Bearing these tricks of the trade in mind as you hit the shops could help you make the most of the sales, ditching the ill-advised investments for some savvy savings.

7 simple ways to save money
How can I rein in my impulse spending?
Six money survival guides