The Use of Scarcity Cues in E-Commerce: Impact on User Experience and Trust
Do Limited-Time Offers Backfire? How Scarcity Appeals Undermine UX and Consumer Trust
Online retailers often use scarcity cues like countdown timers and limited quantity messages to create a sense of urgency and boost sales. For example, see the image below from Booking.com — users are rushed to make a decision as only a limited number of rooms are available at a particular price.
However, research suggests these techniques may negatively impact user experience and erode consumer trust. In this article we will discuss psychological theories of scarcity, how it’s being used, and the impact it has on the user experience. In particular, we’ll focus on a new study by Tuncer et al. (2023) that provides empirical evidence on how scarcity cues affect perceptions of website benevolence, task load, and emotions during online shopping.
Theories of scarcity
The use of scarcity cues is grounded in psychological theories of scarcity. Research has shown that product scarcity can affect how valuable they are perceived to be. Specifically, products and services are seen as more valuable when they are in short supply.
In addition to this, products that are hard to find are viewed more favourably when their scarcity is intentional and demand-driven rather than unintentional and circumstantial. In other words, consumers react more positively to a product being scarce because it is popular and sought-after, as opposed to scarce because of a random supply issue. This suggests that consumers' preference for scarce goods stems in part from their perception of the reason behind the shortage, not just the scarcity itself.
Marketers regularly leverage this bias by artificially limiting availability to increase desirability and motivate quicker purchases (Aggarwal et al., 2011). For example, stating that only one or two items are available to push people to make a quick decision.
However, scarcity cues are increasingly considered “dark patterns” - manipulative design elements that harm user experience (Mathur et al., 2019). Dark patterns exploit human biases against the user’s interests. While at times they can be effective for driving conversions, they can also increase aggression, impulsive buying, and mistrust (Kristofferson et al., 2017; Luguri & Strahilevitz, 2021). In extreme circumstances scarcity cues can lead to extreme events such as the death of a Wal-Mart worker from a stampede of shoppers in 2008 on Black Friday sales.
Latest Research
Tuncer et al. further investigated the effect of scarcity cues by developing three versions of an e-commerce clothing site using a standard template; The limited-time condition had countdown timers on products, the limited-quantity version showed a stock progress bar, and the the control site had no scarcity cues.
They recruited 202 participants, gave them fictional personas and then asked to shop for suitable clothing items for each persona. This was to reduce personal biases. After the tasks, they completed the NASA Task Load Index, Website Trust benevolence scale, and User Experience Questionnaire (UEQ) short form.
One of the major findings of the study was that limited-time scarcity cues increased negative emotions like frustration, stress, and irritation compared to the control condition without any scarcity messaging. This aligns with prior research suggesting countdown timers and other urgency prompts can annoy users and arouse aggressive feelings if overused (Kristofferson et al., 2017).
In Tuncer et al.’s study, these negative reactions were captured by the frustration subscale of the NASA Task Load Index. The scale assesses a range of affective responses beyond just frustration. Analysis showed significantly higher frustration scores when the site had countdown timers versus no scarcity cues. This provides clear evidence of the emotional toll of limited-time nudges during online shopping.
Relatedly, the presence of countdown timers worsened the pragmatic quality of the user experience compared to the control. The UEQ pragmatic measure indicates how easy and frictionless it is for users to complete tasks on the site. The finding suggests limited-time cues may act as visual clutter that makes navigation more difficult. It aligns with past research showing attention-grabbing elements can hinder usability (Van der Lans et al., 2021).
On the other hand, limited-quantity scarcity cues did not significantly affect frustration or pragmatic quality versus control. This indicates limited-quantity messages may be less disruptive and arbitrary-seeming when shopping. However, they did lower the hedonic score, which covers entertainment and aesthetic appeal. This hints that “only 5 left!”-style scarcity claims still cheapen the experience.
Both cue types negatively affected perceptions of vendor benevolence according to the trust scale. This reveals that even fictional implementations of scarcity are seen as opportunistic ploys rather than credible claims. The finding comports with mounting awareness of how dark pattern nudges seek to manipulate users (Bongard-Blanchy et al., 2021).
Implications for UX (and beyond)
This study provides additional evidence that scarcity cues negatively impact user experience. The heightened frustration and reduced benevolence ratings indicate these tactics are perceived as manipulative and have a negative impact on user experience.
For designers and retailers, avoiding scarcity cues could improve perceptions of benevolence and ease-of-use. Where used, scarcity claims should be specific and verifiable to build trust.
The lack of task load effects suggests users may be habituated to scarcity cues. However, the emotional and trust impacts remain concerning. More research is needed on counteracting these downsides and balancing user experience with business goals.
Existing research highlights the need for transparency and caution when employing these persuasive techniques. Dark patterns risk harming customer relationships, even if they provide short-term gains.
Good one, as always! 👏🏻 Personally, as many others, I have developed a mistrust with scarcity design techniques when I see airlines (easyjet) displaying "only 3 seats left" for bookings that are 6 months out because that is just impossible. That tells me it's BS. Same with Booking.com. 😡 So, yes, I agree, rather than enhancing the user experience, it leads to an erosion of trust with users. If you're interested, I wrote an article a while back on Medium about "Exploring the ethics of persuasive design" https://uxdesign.cc/exploring-the-ethics-of-persuasive-design-fc06ef847ebe