1. The Shop Was Empty. I Lined Up. Suddenly the World Showed Up
Nobody in front of the shop.
"Looks empty," I think, and I get in line by myself.
A few minutes later I glance back.
People. People. People.
Another day. Another empty shop. I line up, someone gets in line behind me, then more people.
After this happens a few times, you can't help wondering.
"Wait, am I not a customer at all? Am I some kind of line summoner?"
Short answer: this is nowhere near proof of a superpower. But the underlying idea, that people already waiting make it easier for the next customers to step in, is a pretty solid finding in consumer behavior, behavioral economics, and queueing research.
In other words, it's not all in your head.
2. The Short Version: Yes, a Line Can Really Attract More Line
Here's how the research stacks up.
| Hypothesis | Where it stands in research | Verdict so far |
|---|---|---|
| A shop with people waiting attracts more customers | Field studies and theory exist | Fairly well supported |
| People who don't know a shop rely more on other people's lines | Field study exists | Strongly supported |
| Even a difference of just one person can favor the longer line | Mathematical model exists | Holds under certain conditions |
| Waiting time can signal popularity or quality | Several experiments | Supported |
| An attractive first customer makes the effect even stronger | Indirect evidence | Plausible but unproven |
| "A line forms specially because I join" | No personal data | Unproven |
In everyday language, "social proof" gets the idea across. Researchers break it down a bit more, into observational learning (learning by watching what others do) and information externality (one person's choice quietly giving useful information to everyone else).
So when you arrive later, you don't necessarily see a line as just an obstacle.
You may read it as a free review: "Maybe these people know something I don't?"
3. Why Going From 0 to 1 Isn't Just "One More Person"
A shop with zero people has a strange lack of information.
"Is it even open?"
"Is this where I'm supposed to wait?"
"Is it unpopular?"
"Is it safe to go in?"
"Is the place next door the better choice?"
But the moment one person stands there, that one person starts explaining all of it, without saying a word.
It's open. This is the entrance. You wait here. Somebody chose this place.
One human being starts doing the job of a sign, a guide board, a review site, and a floor marking all at once.
In the queue-choice model by Veeraraghavan and Debo, if service speed and other conditions are the same, having just one more person in one line can make joining that longer line the rational choice. On top of that, the private information of the very first customer, when both shops are empty, can decide which shop ends up busy.
This is a very "first person" kind of problem.
From the shop's point of view, you're not a customer.
You're seed liquidity.
4. Research Also Shows: The Less You Know a Shop, the More You Watch Others
Raz and Ert observed lines at similar restaurants located close together, and how new customers chose between them. Longer lines went with more new customers joining, and the link was especially strong in tourist areas, where many customers don't know the neighborhood.
In 2019, Fishman, Fishman, and Gneezy watched two similar-looking food stands side by side on a university campus. At the start of the school year, when there were lots of new students who knew little about the stands, newcomers tended to pick the more crowded one. Once students got to know the stands, that tendency vanished.
That's a step more interesting than plain "everyone's going, so I'll go."
When you don't know, you borrow other people's choices as information.
Across four experiments, Giebelhausen and colleagues showed that waiting itself can work as a signal of quality, and under some conditions it raises purchase intent and satisfaction.
Munichor and Cooke, through field research at a café plus experiments, also showed that when a long wait can be read as "other people want this too," it can lead to more buying and consumption.
So a line is an obstacle and an advertisement at the same time.
A digital sign made out of humans, with a zero electricity bill.
5. So Does It Work Even Better if the First Person Is Attractive? This Part Is a Hypothesis
This is fun, but we need to draw a line.
As far as I could check this time, I couldn't find a solid study that directly tested whether "an attractive person at the front makes the line grow."
There is neighboring research, though.
In Langlois and colleagues' meta-analysis on physical attractiveness, people rated as attractive were, on average, judged more positively and treated more kindly.
Also, Argo, Dahl, and Morales ran three field experiments in real stores and reported "positive consumer contagion": products seen as touched by a very attractive person were rated higher under certain conditions. That study had conditions too, such as the gender relationship between the attractive person and the evaluator, so it's not a simple cure-all effect.
What this suggests is that if the first person looks like someone worth following, thanks to being clean-cut, well dressed, having a good vibe, or carrying themselves with confidence, then their choice might become a slightly stronger signal.
But that's inference.
It is not a research result like "a good-looking guy in line boosts sales by 30%."
So the scientific way to put it is:
The attractiveness-boost theory: possible. But not directly proven for lines.
Shop: "Can we use attractive early customers as free billboards?"
Research: "We never said that."
Shop: "Tch."
6. The Biggest Counter-Hypothesis: You're Not "Summoning" Anyone, You're Just 30 Seconds Ahead of the Wave
Ignore this and the whole thing turns into an urban legend.
People don't arrive completely at random.
Lunch breaks, dinner time, train arrivals, the end of a movie or event, traffic lights, rain, break times: customers tend to come in clumps.
The moment you think "time to eat," the ten people around you may be looking at the same clock.
So when you see
Shop: 0 people → I line up → 2 minutes later: 8 people
it feels like "I called in 8 people," but in reality
you may simply have arrived at the front of a wave of demand 30 seconds before it hit.
There's also a chance that you unconsciously pick shops that are likely to get popular. If you choose the same shop as everyone else ahead of time because of the location, the smell, the menu, the look, the price, or how the staff move, then the cause isn't "you." It's "everybody read the same clues."
And a long line isn't always a plus. If the cost of waiting is big, customers leave, and sometimes a line signals "this place is slow" instead of "this place is popular."
A line is advertising, but once it gets too long, the advertising evolves into a physical attack.
7. "But It's Happened Many Times Already." How Much Does That Count as Evidence?
If it's happened several times, it is naturally more interesting than a single coincidence.
But what you need is not the hit count but the denominator.
It's not enough to remember that
- 10 people came after I lined up
- 5 people came after I lined up
- a line formed again after I lined up
You also need the number of times
- I lined up and nobody came
- the crowd grew even though I hadn't lined up
According to the availability heuristic studied by Tversky and Kahneman, people tend to judge how often something happens, or how likely it is, based on the examples that come to mind easily.
"A line formed behind me again lol" sticks in your memory.
"I bought something and went home. Nobody behind me." That gets deleted instantly from the video folder in your head.
So if you really want to test it, run a simple N=1 experiment (a test with just yourself as the subject).
- Record only shops with about 0 to 1 people already there.
- For half of them, line up right away. For the other half, step away for 2 to 3 minutes and watch.
- Write down the time, day of the week, the number of passers-by, whether an event just ended, the weather, and so on.
- Count how many people join after 5 minutes and after 10 minutes.
- Compare new customers per minute between "the condition where I lined up" and "the condition where I hadn't lined up yet."
Even 20 to 30 tries makes a pretty interesting personal observation. It isn't rigorous causal inference, but it's a big step up from "just my memory."
And if a difference shows up, you'll finally be tempted to send the shop an invoice.
Item: seed liquidity provision fee.
8. Final Verdict: Customer, or Free Marketing Staff?
The most reasonable verdict right now is this.
The phenomenon of "a line attracting the next customers" is real.
There is also a logic for why "the first person" matters.
If you've experienced it many times, there's no need to write it off as pure imagination.
On the other hand,
"A particular person summons lines with a unique ability" has not been proven yet.
And about attractiveness: there are general halo effects and spillover effects in shopping settings, but nobody has directly tested them at the front of a line.
So your provisional job title can be this:
Free Seed Liquidity Provider.
Shop: "Not many customers today, huh."
You: "I'll take this, please."
Three minutes later: "The end of the line is over here!"
You: "I only came to buy lunch, though?!"
Whether it's a superpower, we still can't say.
But at the very least, people pay more attention than you'd think to the sight of "someone already chose this."
- Raz, O. & Ert, E. (2008). “Size Counts”: The Effect of Queue Length on Choice between Similar Restaurants. Advances in Consumer Research, 35, 803–804. https://www.acrwebsite.org/volumes/13349/volumes/v35/NA-35
- Veeraraghavan, S. & Debo, L. (2009). Joining Longer Queues: Information Externalities in Queue Choice. Manufacturing & Service Operations Management, 11(4), 543–562. https://doi.org/10.1287/msom.1080.0239
- Fishman, A., Fishman, R. & Gneezy, U. (2019). A tale of two food stands: Observational learning in the field. Journal of Economic Behavior & Organization, 159, 101–108. https://doi.org/10.1016/j.jebo.2019.01.004
- Giebelhausen, M. D., Robinson, S. G. & Cronin, J. J. (2011). Worth waiting for: increasing satisfaction by making consumers wait. Journal of the Academy of Marketing Science, 39(6), 889–905. https://doi.org/10.1007/s11747-010-0222-5
- Munichor, N. & Cooke, A. D. J. (2022). Hate the wait? How social inferences can cause customers who wait longer to buy more. Frontiers in Psychology, 13, 990671. https://doi.org/10.3389/fpsyg.2022.990671
- Argo, J. J., Dahl, D. W. & Morales, A. C. (2008). Positive Consumer Contagion: Responses to Attractive Others in a Retail Context. Journal of Marketing Research, 45(6), 690–701. https://doi.org/10.1509/jmkr.45.6.690
- Langlois, J. H. et al. (2000). Maxims or myths of beauty? A meta-analytic and theoretical review. Psychological Bulletin, 126(3), 390–423. https://doi.org/10.1037/0033-2909.126.3.390
- Tversky, A. & Kahneman, D. (1973). Availability: A heuristic for judging frequency and probability. Cognitive Psychology, 5(2), 207–232. https://doi.org/10.1016/0010-0285(73)90033-9
