Commuters are difficult animals to herd – a fact learned the hard way by Transport for London (TfL), which runs the Underground network as well as buses, trams and boats in the British capital.
In 2016, in an effort to battle station congestion, staff at Holborn station in central London ran an experiment. Rather than follow the long-entrenched rule that tells Underground passengers to stand on the right side of the escalator, leaving the left for those in a rush to walk up or down, they asked commuters to stand on both sides.
There was method to this madness: Holborn's escalator is 24 metres high, meaning 60 per cent of people don't actually bother to climb it, according to The Guardian. Staff figured that standing on both sides could boost passenger flow – and they were right, with 16,220 customers ferried up the standing-only escalators versus the usual 12,745 over the same length of time.
But there was a problem: nobody wanted to break tube etiquette. At the time, commuters were quoted as saying the new escalator rule was "really frustrating" and "blatantly not working". Despite the success moving passengers, the standing-both-sides method hasn't yet been trialled at other tube stations. And it's not only Londoners who are so single-minded: similar escalator etiquette has been challenged in Hong Kong and Japan, where an attempt to get people to stand on both sides also failed.
Such is the power of tube psychology. But what exactly is happening in commuters’ minds in such situations? Why is being asked to stand on an escalator in a certain way so infuriating?
Rory Sutherland, vice chairman of behavioural science consultancy Ogilvychange, says that basic psychology is at play. "By making people stand on both sides, you are actually removing choice from people and they like the feeling of autonomy, even when actually the choices they're making aren't all that different," he says.
Nick Tyler, professor at UCL's centre for transport studies, says we don't want to have to overthink what we're doing while navigating stations, "We only have so much capacity for cognitive processing," he explains. "So basically, in peak hours, people are functioning on a kind of 'autopilot'."
Tyler adds that though the escalator change may have worked mathematically, it "failed psychologically". And this is exactly why TfL runs such trials, as what works on paper doesn't necessarily go as planned once people get involved.
But the maths of the Underground are increasingly problematic, with overcrowding despite passenger numbers dropping slightly, leading to budget shortfalls that can cancel network upgrades, further exacerbating crowding. No wonder TfL hasn't given up trying to improve passenger flow. A spokesperson told WIRED that there are so many little, local experiments happening across the gargantuan network that TfL doesn't even have a record of them all. (The spokesperson added that they also don't like publicising the trials in order to keep the results authentic.)
One trial last summer was noticed by the public, as it involved green lanes painted down one platform of Kings Cross, directing people where to stand to make it easier for those alighting during crowded times. "I think the concept is important: if people cannot leave the train, they block others trying to board," says Tyler. "Trains are running at higher frequencies than before, and it is often not possible to clear the platform of passengers from one train before the next one arrives. The stations are too small so the space for passengers is very restricted."
Results from that study haven't yet been published. A TfL spokesperson noted that, though crowding was alleviated, the trial happened as that particular line added a few extra trains an hour, making benchmarking difficult. (Green instructions on the ground might help lessen crowding, but extra trains certainly will.)
And that's the problem, says Oliver Green, the former curator of the London Transport Museum and the author of The Tube and Designed for London: 150 years of Transport Design. He argues that psychological tricks and smarter wayfinding are only fiddling around the edges of a massively overburdened transport network; the real work isn't in passenger behaviour, but infrastructure.
"The tube is a very constricted environment and there are not many options for getting people through faster," he says. "Back in the 1920s, putting in escalators instead of lifts at new or rebuilt stations made a huge difference, but nowadays you need at least two sets of escalators at busy stations, plus new lifts for disabled access. You can only really relieve the pinch points through major reconstruction, which is expensive and difficult so it rarely happens."
Better design helps, of course. For example, he says, Jubilee Line stations have markedly more organised queues than other lines, because the platforms are enclosed. The train carriage doors meet up with the platform doors, so everyone knows where to stand. That's effectively what part of the "green lanes" trial at Kings Cross was hoping to achieve, but even if commuters know where to queue, there's not always space to do it, he says. "[London Underground's] battle to improve capacity will go on indefinitely and these ‘experiments’ at a few stations will make very little difference," he predicts.
Short of building new stations and drilling tunnels for larger trains, we're stuck, says Simeon Koole, lecturer at the University of Bristol. "I would be reluctant to argue there is anything specific about behaviour that makes it difficult to change, and focus more on particular material restrictions of the tube: the confined space limits the possibilities for redesigning tube cars and platforms and therefore for managing passenger flow and conduct."
That said, Tyler says there are plenty of gains to be had by helping passengers board and depart quickly. "We did a lot of experiments for London Underground and others in relation to passengers at the platform-train interface and it is quite clear that our understanding of what actually happens was pretty poor," he says. "We tend to think about the carrying capacity of trains, but not their capacity to cope with boarding and alighting at stations, which is arguably far more critical."
Shave a few seconds from a train time or improve signalling and you'll improve capacity by increasing the frequency with the same fleet – but that needs better understanding of train and platform design as well as human behaviour. Improvements can stem from doors on the platform as with the Jubilee Line, gap fillers between the platform and train to reduce fears of falling, announcements to move passengers down along the platform, better signalling so trains can get closer together safely, and plenty more.
"We have looked at evening out the spacing and design of doors on trains and opening up the train carriages, and this helps to even out the differences in numbers of passengers waiting at each door," Tyler says. "In the end, the time in the station is dependent on the time taken at the slowest door, so evening out those numbers makes a big difference."
Experiments in customer behaviour to alleviate overcrowding aren't new. Koole references in a paper that station managers in 1919 were struggling to get passengers to board trains quickly enough; the difference between a 25-second load time and the average 55 seconds cost the network ten trains an hour, slicing capacity by a quarter. To speed up loading, Oxford Circus station tried barriers to hold back commuters until passengers had left the train, removing the barrier when it was time to board. It didn't work, as departing passengers started to be "more leisurely in their movements." At Knightsbridge, they tried "organised queuing", but it didn't work at busier stations. Koole says station staff have been telling passengers to move down the platform with megaphones since the 1920s.
Read more: Nobody really knows why the Tube is getting less and less crowded
Even tube carriages were meddled with. In 1915, an experiment introduced doors to the centre of carriages; previously they were only at either end, making it difficult to load passengers. Automated versions were widely rolled out in the 1920s, and the addition of doors at the middle of carriages meant at some curved stations there was a gap between train and platform – hence the introduction of the "mind the gap" warning.
Such efforts to manage passenger flow are possibly why we stand on the right and walk on the left, Koole says. "On the early escalators a handrail cut diagonally across the top from left to right" as passengers stepped off, he explains. The first tube escalators, notably at Earls Court, were designed to push passengers to step off at a diagonal angle, as it helped avoid their shoes and coats being trapped between the escalator and the floor – a problem because of the way that the moving sections disappeared under the floor. There's a theory, Koole says, that the design encouraged the still-remaining stand-on-the-right rule, as those moving more quickly had a more direct route off the escalator.
Not all transport experiments are about crowds and how to avoid them. One famous piece of research took place on New York's subway, where students were tasked with the nerve-wracking job of asking passengers if they could have their seat, without any explanation as to why. It turns out most people will get up and stand if you ask – but it's terrifying to have to ask. No wonder that the London transport authority marks as one of its successes a trial for a "Please Offer Me a Seat" badge – similar to the "Baby on Board" buttons – so that people whose need to sit down wasn't immediately obvious wouldn't always have to explain themselves. TfL says 78% of users found it easier to get a seat with the badge.
And there's more to travel than speed. Getting to work on time is important, but plenty of commuters are happy spending five minutes more on a train in order to get a seat or avoid changing lines, Sutherland argues. That could be one reason why a Wi-Fi based study of passenger routes on the Tube was so surprising, with commuters sometimes opting for convoluted routes with multiple, unnecessary changes or spending longer travelling than necessary. But if you stop assuming speed is our main factor, other passengers' routes only look bonkers because we don't know their motivation – perhaps they'll do anything to avoid Bank station at rush hour, prefer to avoid stairs, or know a colleague takes a certain train and want to avoid small talk.
Proof of the fact speed isn't everything was borne out by TfL's escalator experiment. Making everyone stand was actually faster for passengers to get out of the station, but it neglected the psychological discomfort of breaking existing etiquette. British commuters would rather queue than break rules.
This article is part of our WIRED on Transport series where we explore the challenges and solutions in transport, such as the future of borders after Brexit, the new race to make supersonic travel work and the hover train that never was.
Follow the hashtag #WIREDonTransport on Twitter for all our coverage and click the links below for more stories in the series.
Cheap oil killed sailing ships. Now they’re back and totally tubular
How I, a 26-year-old writer with a crippling existential fear of space, trained to be an astronaut
In China, Alibaba’s data-hungry AI is controlling (and watching) cities
This article was originally published by WIRED UK