Desperate to keep his tenants, the building manager turned to his staff for suggestions. One employee noted that people were probably just bored and recommended installing floor-to-ceiling mirrors near the elevators, so people could look at themselves and each other while waiting. This was done, and complaints dropped to nearly zero.
It's a tale that appears in books and articles about organizational design, though it's not clear whether it's a real story or simply a parable. Regardless, the story offers a powerful insight into one of the most universal, and universally hated, things we do: waiting in line. It suggests that there are hidden and surprising factors that affect how we experience lines.
In the case of elevators, it wasn't the wait that mattered. It was that we got bored while waiting.
While that story has become legend, it was not the first time people started thinking seriously about waiting, or queuing, as academics call it. A Danish engineer named A.K. Erlang developed the first mathematical models of how lines worked in the early 20th century to complement a new device at the time: the telephone.
Erlang's work helped the phone company figure out how many phone lines and operators the old-fashioned central switchboard needed to keep customers from waiting too long. He used probability and statistics to model how bottlenecks form as customers arrive, and how quickly companies need to provide service to keep queues moving. His work inspired the next generation of mathematicians and engineers to take up the subject.
In those early days, engineers were focused solely on efficiency — how to serve as many customers as possible without cutting into a company's profits. It wasn't until 50 years later that researchers began to realize that there were subtler factors influencing people's experience of waiting in line, including ideas of fairness, mismanaged expectations, and the strange and inaccurate way that most people perceive both time and pain.
Interestingly, it turns out that what you hate most about lines probably isn't the length of the wait after all.
The business of lines
The time that people spend waiting in line, and how they feel when they do so, is a big deal for average people and the economy.
Altogether, some people spend a year or two of their lives waiting in line, estimates Richard Larson, a professor who studies queuing theory at MIT. This back-of-the envelope calculation includes less obvious types of queues, like driving in slower-than-normal traffic during a daily commute.*
And the way that businesses manage lines results in easily billions of dollars of gained and lost brand equity and consumer spending. A long and unpleasant wait can damage a customer's view of a brand, cause people to leave a line or not enter it in the first place (what researchers respectively call "reneging" and "balking"), or discourage them from coming back to the store entirely.
Companies have come up with some novel solutions to shorten lines, including charging customers for skipping or advancing in the line. Examples include priority boarding on airplanes and special concession lines for NFL season-ticket holders. These new technologies seem to be cutting down on the amount of time spent waiting in line, though they are unlikely to get rid of waiting altogether.
One strategy that companies can use is distraction. Research suggests that people who have nothing to do perceive wait times to be longer than those who are distracted by reading materials, television or conversation. Mirrors by the elevator, TV screens at the airport, magazines in the waiting room, little knick-knacks to peruse and buy in the supermarket checkout aisle and, of course, smartphones, all take people's minds off of their frustration about being imprisoned in a line.
Larson of MIT — who signs his e-mails with the Bond-villain-esque moniker of "Dr. Queue" — says that Disney is the undisputed master of this technique, designing queues that are entertaining and create anticipation for the ride. The line for one Toy Story-themed ride, for example, features giant murals, oversized toys and a five-foot-tall animatronic Mr. Potato Head, who entertains those waiting in line with a semi-interactive spiel.
"In my book, they’re number one in the psychology and in the physics of queues," Larson says of Disney. The design is so successful that parents with young children can happily stand in line for an hour for a four-minute ride — a pretty remarkable feat, he points out. And of course, the capacity of the line and the ride are carefully calculated to balance customer satisfaction with profits.
One other powerful technique that Disney exemplifies is managing people's expectations for the wait. Disney often gives estimates for how long someone might spend standing in line for its amusements, and these wait times are almost always overestimated, according to Larson's research. Even if the wait time is extensive — an hour, for example — people are pleasantly surprised when they exit the line in 45 minutes, "ahead of schedule." (Larson says this information is a decade old, so it's not exactly clear what process Disney uses today. The company declined to comment.)
Estimated wait times also help to defuse the anxiety, stress and uncertainty that people experience, which research suggests are the most common problems with waiting in line. This anxiety gets especially acute when you can't see or monitor the line — which is why many customer service phone hot lines these days will tell you how many people are waiting in front of you.
Pain and baby-step gains
Have you ever noticed that many of the lines you encounter in daily life are one of two main types? Some businesses have many parallel lines that consumers have to choose among — for example, the lines that typically form behind grocery checkout counters, or the lines of cars at toll booths. Others have one long, serpentine line that everyone waits in, and when you reach the front of the line you are served by the next available register.
Most grocery stores follow the first kind of system, but others don't. Some Trader Joe's and Whole Foods stores offer both options — the traditional grocery store checkout lanes, as well as one single long line that feeds numerous registers — while other of their outlets will use just a single long line.
Fast-food companies are similarly divided. Wendy's famously adopted the single serpentine line shortly after its founding, after realizing that this kind of line required fewer employees. McDonald's chose to stick with many short lines — though now a majority of McDonald's business comes from the drive-through, which is actually a single, serpentine line.
The systems each have advantages and disadvantages. The biggest obstacle to adopting the serpentine line is that you need floor space where the line can form, meaning it doesn't work in all store designs. Often, the lines at Trader Joe's stores in Washington will snake around the entire store, blocking customers' access to the shelves. Some companies also find they need some kind of line manager or automatic system to organize the process.
What about the amount of time each line takes? According to Larson, if both systems are working efficiently, the mean wait time is about the same. However, the variance is larger for the parallel line system than for the single serpentine line — meaning that you could be served very quickly, or have a very long delay.
In practice, the system of many parallel lines also gives rise to inefficiencies — like when customers don't notice that one checkout counter is open — which slows down service. "So, the many-line system can never have a mean queue time less than that of a single-line system," Larson says.
If you do run into a long delay in the parallel line system, that experience is going to be particularly annoying and memorable, especially if you only have a few items in your cart. Research on the psychology of queuing suggests that people have a tolerance for waiting that is proportional to the complexity or quantity of service that they anticipate. In simpler language, if you have a cartload of groceries, you won't mind as much if the person in front of you has one, too. But if you're just buying a few things, their preparation for the end times is likely to annoy you — which is why most grocery stores also have express lanes.
Larson and other queue researchers argue that the single, serpentine line has other, more important advantages. Namely, it seems socially fairer, because customers who arrive first are always served first. Because people waiting in line often value fairness more than efficiency, studies have shown that serpentine lines make customers happier than parallel lines, regardless of the wait time.
That guarantee of fairness eliminates a lot of stress and anxiety. You might not think about it much, but a system of many parallel lines, like at a grocery store checkout or toll booths, can be very anxiety provoking. There's the stress of choosing the shortest line, and then there's the possibility that, for unforeseen reasons, your line will grind to a halt. You can analyze the contents of people's carts all you want, but the person in front of you may still pull out an envelope stuffed with coupons or a giant bag of pennies.
These lines tend to lead to what Larson calls "slips and skips," where people who enter the line first watch those who arrived later overtake them. He says these generate a lot of anxiety and uncertainty, and “the victim experiences more psychological loss than the perpetrator enjoys benefit.” (Those relatively painful experiences end up being more memorable than the relatively painless ones — one reason it seems like the other line "always moves faster.") Here's a wonderful illustration of skips and slips by the artist Ferdinand Lutz:
Many companies made the switch to one serpentine line to "get rid of the stress of queue calculus," as Larson says. Chemical Bank in New York claimed it was the first to switch to one long serpentine line in its bank lobbies in the 1960s. American Airlines and British Airlines were also early adopters of the system.
Another important factor is the speed and pacing of the line. Research by Daniel Kahneman, the psychologist whose work sparked a broad rethinking in economics, argues that consumers waiting in line experience a dual response: They become gradually demoralized as they wait but have a positive response to each forward movement of the queue. Their overall feeling about the experience depends on how these two responses balance out.
Other research by Kahneman on how people remember unpleasant activities suggests that the way we remember a line is heavily influenced by how the experience ends. A line that starts slow and speeds up is very different, and psychologically preferable, from waiting in a line that starts fast and then slows to a crawl.
In one experiment, Kahneman asked subjects to submerge their hands in very cold water up to the wrist — a sensation that is tolerable but hurts. First, they immersed one hand in 14 degree Celsius water for 60 seconds. Second, they immersed the other hand in 14 degree Celsius water for 60 seconds — the exact same experiment — but then kept that hand in the water for another 30 seconds as the temperature of the water was gradually raised to 15 degrees Celsius, a temperature that is "still painful but distinctly less so for most subjects," according to the study.
When people later were given a choice of which trial to repeat, a significant majority chose the latter trial. Even though it lasted for a longer duration and clearly included more pain overall than the first trial, people preferred it because it had a relatively better (or, more accurately, less worse) ending. The study concludes that the duration of the experience doesn't matter that much to people — what matters is the discomfort at the worst and final moments.
As this and other research suggests, our experience of waiting in line is all about perception, and that can be easily manipulated.
Larson agrees that how we feel about waiting in line is often an issue of perspective. He points out that, when people go out to a movie and then dinner with friends, some could see the hours spent in a movie theater watching a movie as essentially "being in queue for dinner." "So if you’re a really negative person you say, 'Gee, I’m in queue for hours' ... I mean, a really negative person would say, 'I’m in queue for death!'" Larson says. "So a lot of it is a matter of attitude."
Note: A previous version of this article incorrectly implied that Disney charges users for FastPass. The article has been corrected.
*Here's how Larson explains his estimate that some people spend 1-2 years of life in line: "My judgement is that for many Americans, especially those who commute to and from work in cars every day, that the great majority of their total queue time in life is the time in traffic congestion. The 'queueing' here is more than just time spent waiting at stop signs and traffic lights. If the speed limit of your road is 40 MPH and you can only move at 20 MPH — due to slow moving traffic, then you are losing 20 miles of travel during each hour of this slow movement. That is also queue delay. It takes you twice as long to drive while moving then it would if there is no traffic congestion. So, for instance, suppose that a home-to-work trip on a Sunday morning takes you 30 minutes. But on a working weekday it takes you 60 minutes. That corresponds to 30 minutes each day, each way, of traffic-caused queueing — 60 minutes of traffic queueing each day, or 300 minutes each week. If you make reasonable assumptions about 5 days a week of driving like this, both ways, for an entire career, then one comes up with figures of one-to-two years of your waking life spent in queues, mostly rush hour traffic queues and slowness which is equivalent to queueing."