On the self-select screen of bakery items before me, the difference was just 50p (65 cents) between a plain croissant and an almond one. While I struggled to identify baked goods, juggling my already half-full shopping bag (placing it on the machine had already once sent it into meltdown), at least three people had sailed through the human-operated checkout. I was flustered, I was annoyed. The almonds had nearly all fallen off anyway.
Retailers tell us that self-checkouts are all about providing more choice, convenience and speed, and some consumers may embrace the shorter queues they can bring. However, it can be very frustrating when they go wrong. One (admittedly unscientific) 2014 poll found that 93% of people dislike them. What’s more, they even drive some shoppers to theft.
So what’s the story behind the proliferation of these machines? And what can be done to improve our experience of using them?
It all started with the automated teller machine, first invented in London 50 years ago, in 1967. A few decades later, the self-service till was invented by David R Humble, inspired by standing in a long grocery checkout line in south Florida in 1984. The tills became popular in the 1990s. By 2013, there were over 200,000 in stores throughout the world and their numbers are expected to reach 325,000 by 2021.
At some stores, there may be no more than one checkout manned by a human
It’s easy to see why they’re so popular with vendors: having customers do some work themselves means less overhead. At airport check-in, for instance, the cost to process a passenger through an electronic terminal (14 cents) is a fraction of what it costs the airline with a staffed desk ($3).
But what’s the benefit for consumers? If there are five self-checkouts to choose from instead of queuing for one human being, clearly they will reduce waiting time. However, if the shops employed five more staff, the experience could be quicker. As part of her campaign to curb the increasing dependence on self-checkouts, journalist and BBC broadcaster Jenni Murray timed how long it took to buy the same items at both staffed and self-service tills in eight major shops. In every instance, the staff checkout was faster. Her anecdotal experiment did include verification-needed items, but she’s not the only one to come to this conclusion.
So, no faster then. No problem, say retail experts and suppliers, thanks to a handy phenomenon known as “wait-warping”: when you’re more actively involved in the transaction, it appears to progress quicker. How very convenient: for the retailers.
But not all shoppers are fooled, so vendors have invested in plenty of strategies to increase our liking for self-service. A popular tactic is to position the tills closer to the exit, providing the subtle suggestion that your transaction will be faster.
Changing the machine’s voice is another ploy. The supermarket Tesco, for instance, dispensed with the unloved voice that chastised customers for an “unexpected item in the bagging area”. It also replaced the machine’s “irritating and bossy” voice with a different one in response to customer feedback (it is careful to point out). And it didn’t stop there. For Christmas 2015, customers were treated to Santa booming "Ho Ho Ho Merry Christmas!” Suffice to say, the Twitter response to this act of seasonal goodwill was not as positive as expected.
Another UK supermarket, Morrisons, also tried out a number of voices, settling on Wallace and Gromit voice actor, Ben Whitehead. But telling shoppers not to get their “tinsel in a tangle” was not enough to safeguard the future of self-service at the store. The company eventually heeded the 67% of customers who complained that they were anxious about using the machines, and engaged an extra 1000 staff.
Other nations have resorted to marketing campaigns, portraying the tech as fun and cool.
And some retailers have attempted to provide incentives. Take McDonald’s: as well as being quick to use, its self-service terminals allow the fast food chain to display its full menu and make it easy to customise burgers. In the States, you even get free sauce.
Have no illusions, there’s canny strategising at work here too: in a 2004 experiment, McDonald’s found that we spend an average of 30% more when we're not fretting about the person behind the cash register judging our choices.
Leigh Sparks, professor of retail studies at the University of Stirling in the UK, says retailers could do a lot to avoid dissatisfied customers simply by offering choice. “If consumers feel the retailers are doing it purely to save costs, and not to better service for the customer, then they react adversely to it," he says. "Where, as in some of the large grocery stores, you see that you’ve got a choice – self-scan as you go, ‘10 items or less’ express queue, standard queue and self-service checkout – then, as the consumer, you’re in control of which journey you want.”
Retailers would also be wise to take heed of cultural factors in the countries they install self-checkouts. For instance, despite its reputation as an automation-loving nation, self-service shopping wasn’t big in Japan until fairly recently. The importance of omotenashi – elaborate courtesy – meant that retailers held off on self-service, preferring to focus on improved staff efficiency.
But shortcomings in the design of many a checkout are also leaving us shortchanged: ergonomic issues include poor placement of the cash dispenser (inconveniently situated beside your knee-cap) and the fact that cashback is issued only after the receipt, and emerges from a different area of the machine. This confounds many a shopper and results in as much as £2.5m a year being left in self-service dispensers.
And where is the back button? In some cases, a mistake can abort the whole process with no indication of what went wrong. Instead, the machine publicly shames you (a strong de-motivator), even though your only error may have been to do something it doesn’t understand.
Up to now, less thought has been given to re-designing self-service machines than encouraging users to adapt to the machines. There are signs that this is about to change.
The world market leader in self-service checkout technologies is US-headquartered NCR, which supplies nine out of 10 UK retailers. According to Dusty Lutz, the company’s vice president of ‘store transformation’, the new generation of self-service checkouts will provide more “elegant, streamlined solutions.” For instance, by the end of the year the company is rolling out technology making it easier for shoppers to scan vegetables and fruit. “Instead of looking up an apple in a menu,” explains Lutz, “the system will scan and recognise that it’s an apple, and will present you with items of a similar shape and colour, so you can select the right one.”
They’re also working on tech that will reduce the need for staff to verify a raft of items from alcohol to aerosols. Nearly half the respondents in a 2014 survey (by online community group, Viewsbank) said they needed assistance every time they used a self-service till. But getting the go-ahead for prior verification entails gaining customer consent, and with that comes a host of trading legislation. It won't happen anytime soon.
But we will see new, improved models: hybrid systems, “belted checkouts” (self-checkouts with conveyor belts), and sensors – all to warn you if you haven't taken all your change, and “intelligent cameras”, to prevent items already in your shopping bag letting off the dreaded alarms.
So, more tech – not less. In fact, Amazon recently opened a fully automated store, using a mixture of computer vision, artificial intelligence and sensors to dispense with checkout altogether.
In the short-term, however, don’t expect traditional self-service checkout to disappear. But will improvements – such as prior verification, more sensors and cameras – be welcomed by consumers? Or will they be seen as further incursions on our privacy? Advances in the self-service sector will come at a cost: in offering to ensure a more seamless experience, vendors will further encourage us to give up personal details.
But Sparks is also seeing signs of a very different approach to retailing altogether. “It’s symptomatic of a swing back, away from the big technology side,” he says. “You see it in the food markets, the locally sourced community grocers and the social supermarkets that are beginning to pop up. Countering the technology – like Amazon’s store or the 24-hours self-service cafe. It’s an experience that’s more authentic.”
Join 800,000+ Future fans by liking us on Facebook, or follow us on Twitter.
If you liked this story, sign up for the weekly bbc.com features newsletter, called “If You Only Read 6 Things This Week”. A handpicked selection of stories from BBC Future, Earth, Culture, Capital, and Travel, delivered to your inbox every Friday.