Chapter 17: Social proof

This category of deceptive pattern involves taking advantage of the social proof cognitive bias, in which people tend to follow the actions of others in order to determine their own behaviour. There are two main types of social proof deceptive patterns: the activity message deceptive pattern, and the testimonial deceptive pattern.

The activity message deceptive pattern

We’ve all seen an activity message before. It’s a little notification that appears on an e-commerce store that tries to persuade you to make a purchase by showing you some sort of message about social activity. Of course, if the message is true then it’s a perfectly acceptable practice. It can be quite useful to know what products are popular in a store – it’s similar to seeing a queue on a street outside a shop, or seeing lots of shoppers holding the same item when queuing to check out. It’s a feature you get for free in the real world, but it’s very easy to fake online. The example below was shared by Henry Neves-Charge on Twitter in 2017.1

Screenshot from Twitter showing a tweet from user Henry Neves-Charge, who tweets ‘This sort of stuff needs to stop. It’s a lie and a dark pattern. See it on almost every ecommerce site’. Beneath is a screenshot of the Etsy website showing a message ‘Other people want this. 3 people have this their carts right now’ below a large, orange button labelled ‘Add to cart’. Over the image is scrawled ‘STOP’ written by hand.
Twitter user Henry Neves-Charge alleges that Esty uses the activity message deceptive pattern.

Fake activity with Beeketing’s Sales Pop app

If you don’t have the time or the skills to build your own deceptive patterns, you can actually buy plug-ins for your website that let you add deceptive patterns very easily. As I explained earlier, the Shopify app store sometimes contains a few of them. These apps manage to sneak in by offering tools that can be either used legitimately or configured to deceive users. Other e-commerce platforms have the same sort of problem, including BigCommerce, Weebly and WooCommerce.

In 2019, Shopify removed fourteen apps from its app store, many of which could be configured to deliver deceptive patterns with just a few clicks.2 Twelve of them were provided by a company called Beeketing. Here’s one of the Beeketing apps: Sales Pop. It causes an activity message overlay to appear on screen containing claims like ‘9 customers have bought item x together with item y’ or ‘Alycia in San Francisco just bought item x 4 minutes ago’.3

Promotional representation of Beeketing’s Sale Pop app. A stylised laptop computer screen shows a generic online footwear store with a pop-up message stating ‘9 customers have bought Fire Wood Stack together with Reebok Crossfit’.
Stylised depiction of the Sales Pop app, from the Beeketing website.

What’s surprising is that Beeketing actively encourages store owners to set this up deceptively. In the Sales Pop app’s support...

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Since 2010, Harry Brignull has dedicated his career to understanding and exposing the techniques that are employed to exploit users online, known as “deceptive patterns” or “dark patterns”. He is credited with coining a number of the terms that are now popularly used in this research area, and is the founder of the website He has worked as an expert witness on a number of cases, including Nichols v. Noom Inc. ($56 million settlement), and FTC v. Publishers Clearing House LLC ($18.5 million settlement). Harry is also an accomplished user experience practitioner, having worked for organisations that include Smart Pension, Spotify, Pearson, HMRC, and the Telegraph newspaper.