Rarity bias: what is rare is expensive... especially in our eyes (and how to capitalize on it)
Have you ever felt that rush of adrenaline when you saw “limited edition” on a product you wanted? Or this urgency to buy the last item on the shelf, even if you hesitated a minute before? If yes, you have been affected by the rarity bias. This powerful psychological lever makes us perceive what is difficult to obtain as having more value. From collectibles to fleeting promotional offers, rarity turns the ordinary into the desirable. In this article, we explore the mechanisms of this bias, how it has been identified, and above all, how you can use it — intelligently and ethically — to make your marketing and sales offers irresistible. Get ready, because what's rare... it's also a gold mine of persuasion!
Cognitive biases are powerful tools to make the way you deliver a message to your target audience more effective and to convince them to trust you. However, it is extremely important to use them ethically. Any use of these concepts that would go against the interests of your customers would not only be dishonest but also, in the medium term, extremely harmful for your brand.
Definition and origin of the rarity bias
What is the rarity bias?
Rarity bias is a psychological principle in which we tend to assign a higher value to objects, services, or opportunities that are perceived to be in limited quantity, difficult to acquire, or available for a limited time. The rarer something is or seems to be, the more valuable and desirable it seems to us. This bias is based on two main mechanisms:
- The value heuristic : We often use availability as a mental shortcut to judge quality. If it's hard to get, it must be good.
- Psychological reactance : When our freedom to choose is threatened (for example, by the impending disappearance of a product), we react by wanting that object or opportunity even more to reaffirm our freedom. It's the famous “run away from me, I'm following you.”
Robert Cialdini, in his essential work Influence and Manipulation, identifies rarity as one of the six pillars of persuasion.
How has the rarity bias been demonstrated?
One of the most cited demonstrations is the “cookie box” experiment carried out by Stephen Worchel, Jerry Lee, and Adewole Adewole in 1975. The researchers presented participants with two boxes of identical cookies. One contained ten cookies, the other only two. Although the cookies were exactly the same, participants rated the cookies from the nearly empty box as being of better quality, more desirable, and even more expensive than those from the full box. Experience has even shown that the newly created rarity (going from ten to two cookies) made cookies even more attractive than those that were rare all along. Simple, elegant, and awfully speaking: the fewer there are, the more you want.
Example of a rarity bias used by a company
Imagine a company that launches a very specialized internal training program, designed to train its future leaders: the “Excellence Program”. To access it, the conditions are strict and, above all, the number of places is deliberately limited to fifteen participants per year for the entire company. This scarcity of seats is not only used for logistical purposes; it immediately gives the program increased prestige and attractiveness. Employees will scramble to be selected, seeing this opportunity as more valuable precisely because it is selective. Success within this program becomes an internal status marker.
How can we fight against the rarity bias?
Not being trapped by the artificial emergency requires a bit of self-control and analysis:
- Recognizing emotion: Rarity often triggers an emotional reaction (excitement, anxiety about running out). Take a moment to identify how you are feeling.
- Evaluate the object on its intrinsic merits: Does this product/service really meet a need or a profound desire, regardless of its availability? Would it be as attractive if it were available in abundance?
- Questioning the source of scarcity: Is it real and justified (e.g. limited artisanal production, rare natural resources) or is it a marketing tactic (e.g. “limited stocks” on a mass product)?
- Compare with alternatives: Are there other options, perhaps more abundant but just as qualitative?
- Give yourself a period of reflection: If there is a lot of pressure, try to postpone the decision. The emergency often wears off over time.
For businesses, ethics is crucial: scarcity must be authentic or clearly presented as a one-time promotional offer. Misleading on real availability can seriously damage trust.
Application of rarity bias in marketing
Marketing is the kingdom of orchestrated rarity. It is a powerful tool for creating desire and accelerating decisions.
Example 1: Limited editions and capsule collections
From Air Jordan sneakers in an ultra-limited series to capsule collections from major fashion designers for popular brands, including “special edition” Nespresso flavors: the principle is the same. By limiting the quantity produced or the length of availability, immediate desirability is created. Items become trophies, status markers for those who succeed in obtaining them. Simply owning something that few people have increases its perceived value (and often its resale value!).
Example 2: Flash sales and offers with a (very) limited time
“48 hours to take advantage of -50%!” , “Exclusive private sale until midnight tonight.” These offerings create a temporal rarity. The customer knows that they have a very short window of opportunity to benefit from an advantage. The fear of missing out on this bargain, combined with the time limitation, leads to a faster purchase decision. The countdown timers displayed on e-commerce sites visually reinforce this urgency.
Example 3: Indicators of low stock and exclusivity
“Only 2 items left!” , “Only 5 rooms left at this rate!” , “Access for premium members only”. These mentions signal that the opportunity is about to disappear or that it is not available to everyone. The fear of seeing the product sold out or of not being part of the privileged circle can be a powerful buying driver. Booking.com, once again, excels in the art of manipulating these indicators.
Applying rarity bias in the sales process
In sales, especially in B2B where personalization and value are key, scarcity can be a powerful argument.
Example 1: Highlighting the exclusivity of the offer or service
“Our 'Performance' support is an offer that we only offer to a very limited number of customers each year, because it mobilizes our best experts over a long period of time.” By positioning an offer as selective, you increase its perceived value and the feeling for the client that they are accessing something special. This also often justifies a higher price.
Example 2: Highlighting the limited availability of specific expertise or resource
“Our main consultant on AI applied to your sector, Dr. Expert, has a very busy agenda. If you want him to personally manage the strategic phase of your project, it would be a good idea to book his intervention as soon as possible.” Scarcity is not about the product itself, but about access to a key human resource, which can speed up the decision if that expertise is crucial for the client.
Example 3: “Unique lots” or ephemeral special conditions
“We currently have a remainder of 3 licenses of our old Pro version, which we are offering at a 40% discount until the stock runs out, before the final transition to our new price range.” or "For the next 5 companies that commit to our XYZ solution this month, we are including the advanced integration module for free, worth Z €.” These offers create a one-time and limited opportunity, encouraging not to postpone the decision.
The questions we get asked the most about the rarity bias
Does the rarity bias work on everyone the same way?
Overall, yes, it is a fairly universal bias because it affects deep instincts (competition for resources, value for what is difficult to obtain). However, the intensity of the reaction may vary depending on the individual, their experience, their level of awareness of the bias, and of course, the rarity object itself. Someone who collects watches will be more sensitive to a limited edition watch than to a promotion on canned goods.
What is the main difference between rarity bias and FOMO (Fear of Missing Out)?
Although they are often linked and reinforce each other, they are distinct. The rarity bias focuses on the increased value of a object or opportunity due to its low availability (e.g. “This diamond is precious because it is rare”). FOMO is social anxiety to miss a experience, event or information that others live or own (ex: “All my friends are at this concert, I have to go so as not to miss anything”). The scarcity of a product can lead to FOMO, but you can have FOMO for events that are not intrinsically “rare” but just popular at a given moment.
Is creating “false rarity” a viable long-term strategy?
It is technically possible (e.g. pretending that a stock is low when it is full), but it is a very bad idea in the long run. If customers discover the deception — and they often end up doing so — brand trust is severely shaken, if not destroyed. Authenticity is a much more valuable currency. An authentic rarity (real limited edition, really low stock, clearly dated promotional offer) is perceived as legitimate. False scarcity is a manipulation that comes at a high price.
In conclusion, the rarity bias is a powerful persuasion tool because it draws on deep-rooted psychological reflexes. Used with transparency and relevance, it can legitimately increase the attractiveness of your offers and encourage your prospects to take action. The art is about creating authentic desirability, not artificial frustration. After all, who doesn't dream of finding the rare pearl? And you, what is the last “rare” product that made you succumb?
