📘 5 Psych Studies for Consumer Social

Applications for Scarcity Bias, IKEA Effect, Hick’s Law, Bandwagon Effect, and Mere Exposure Effect

Yo! ✌️ I’m Brett! I am a Product Manager and former Cognitive Science researcher. Social Studies is a semi-weekly newsletter for people building great products for humans. It includes recaps of what happened on Tech Twitter every week plus deep analysis using frameworks from Psychology, Economics, and the other Social Sciences.

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✨ TLDR

  • Scarcity Bias - Users want things that are (suddenly) scarce (due to high demand). Waitlists increase perceived product value. Verified badges incentivize usage.

  • IKEA Effect - Users place higher value on things they (help to) create. To drive the value of any product or piece of content, proof of work is required.

  • Hick’s Law - The time it takes users to make a choice increases as the number of choices increases. Remove choices in user flows in increase completion rates.

  • Bandwagon Effect - Users adopt the beliefs, ideas, fads and trends that are already been adopted by others. Tik Tok is so successful because it enables mimicry at scale.

  • Mere Exposure Effect - Users prefer things that they are familiar with. Use UI, color palettes, and language that users are familiar with.


🍪 Scarcity Bias

In 1975, psychologist Stephen Worcliel ran an experiment asking subjects to rate the value of cookies that were in abundant or in scarce supply. There were three key findings:

  • Cookies were rated as more desirable when they were in scarce supply

  • Cookies were rated as more desirable when their supply changed from abundant to scarce (vs when it was constant)

  • Cookies were rated as more desirable when they were scarce because of high demand (vs being scarce because of an accident)

Users want things that are (suddenly) scarce (due to high demand)

What does it mean for consumer social products?

Use waitlists to drive adoption

One of the most recent popular applications of Scarcity Bias is waitlists. Waitlists improve the perception of an application by artificially limiting the number of people who are able to join it. Asking users to retweet or promote content to improve their standing on the waitlist also increases the perception that the scarcity is connected to high demand. Randomly giving users invites to share with their friends also propels this further.

Verified badges can drive adoption for top creators

Virtually every social network has a verification badge. While their main purpose may be to prove the identity of celebrities, their scarcity increases their desirability everyone who isn’t one. This in turn incentivizes users who want verification (emerging influencers) to take actions to get it (posting more).

To understand how much people care about being verified, do a quick search for “verified” on Tik Tok. Getting verified is one of the biggest milestones and proudest moments for influencers on the platform. There’s even a “verified” song.

🔧 IKEA Effect

In 2011, Michael Norton, Daniel Mochon, and Dan Ariely ran a study at Harvard Business School asking people to price IKEA furniture either they assembled or was preassembled. They found that people were willing to pay 63% more for furniture they assembled themselves. Further studies validated these findings.

Users place higher value on things they (help to) create.

What does this mean for consumer social?

Have users set up their profiles

Inputting profile information is one of the easiest ways to execute the IKEA effect. The more a user completes their profile the higher value they will place on the product. You can take this further by allowing for more customization like color schemes.

Create customizable spaces

Reddit, Clubhouse, Facebook (Groups) and other open-ended platforms do a great job of making users feel ownership over sections of the product. As moderators and their communities put in work to set guidelines, programming, etc. they place higher value on the platform at large, since they put the work in to create it.

Require effort for content creation

The classic “come for the tool, stay for the network” strategy has been employed by tons of content creation apps over the years, but many actually fail to create networks. Why?

Content that doesn’t require much effort from users to create (e.g. pick a photo or video and press a button) isn’t valued as much as content that does (e.g. lip sync a song, frame this photo). This is one of many reasons why Tik Tok has been such a success and style transfer apps like Prisma have not.

As AI-assisted creativity apps become more popular, this is going to be an increasingly important concept for founders to internalize.

Further reading: IKEA Effect: When Labor Leads to Love

⏱ Hick’s Law

In 1951, William Edmund Hick ran an experiment where people had to press a button corresponding to a lamp when it lit up. He found that as the number of lamps increased, the speed participants would press the correct button diminished.

The time it takes users to make a choice increases as the number of choices increases

What does this mean for consumer social?

Remove non-critical decision-making during onboarding

When new users sign up for your product, it’s crucial to get them to that “magic moment” as soon as possible. It’s the moment when they see the value of the product - for Facebook that was adding 7 friends, for Clubhouse it’s getting on stage for the first time.

Hick’s law states that the more choices you give users during onboarding, the slower they take, and thus the more likely they will give up. Users are quite fickle after all.

As an example, Twitter removed picking a username from the onboarding flow. Why? There are trillions of permutations of letters and numbers to choose from - that’s a lot of choice that really stalls out users during onboarding.

If you have ever tried to decide what to eat for dinner, you know how debilitating choice can be.

Constrain expressivity

For communications products where number of messages sent to close contacts is one of the key drivers of retention, adding more communications features might actually be a bad thing. More GIFs, emojis, etc. increase the number of choices sending a message, which increases the amount of time it takes to send the message, and thus increases the likelihood that message is never sent.

Instagram Stories executes this well. While there may be a lot of options for stickers, fonts, etc., these choices are a few clicks away and the defaults suffice for most users. This is an example of when burying features is a good move.

Further reading: The Paradox of Choice by Barry Schwartz

🚌 Bandwagon Effect

The phrase “bandwagon” first emerged in 1848 when Dan Rice, a literal circus clown of the time, used his bandwagon to drum up attention for his political campaign. Numerous psychologists, economists, and philosophers have studied this phenomenon since then - René Girard (Mimetic theory) and Robert Cialdini (Social Proof) for example. The idea is this:

Users adopt the beliefs, ideas, fads and trends that are already been adopted by others.

What does this mean for consumer social?

Enable mimetic content

Since humans are mimetic creatures, and social products enable humans to communicate, it follows that features that enable humans to be more mimetic prevail. In fact this is one of the biggest lessons from Tik Tok. Users want to recreate what they see on social media and Tik Tok allows them to do exactly that by creating their own videos from the audio of any other video.

Monkey see, monkey (pull the same audio, stage the scene similarly, etc. and) do.

Use social proof to drive behaviors

Whenever there’s a behavior you want users to adopt, it’s important to show that other users are also doing that behavior.

Tik Tok is great example here. Instead of showing tool tips or notifications explaining how to use Tik Tok effectively or suggesting they take a break (if they’ve been on for a while), Tik Tok shows UGC (or seemingly UGC) to convey the same message.

This works because it makes the message seem to be supported by a lot of other users (particularly when the UGC has a lot of likes and is actually UGC).

Avoid social proof bias towards existing winners

One of the biggest problems in social media is that winning begets more winning. The more likes a piece of content has, the more likes it is likely to get. The more followers someone has, the more followers they are likely to get.

This is partially because of the user/content are genuinely high quality and partially because seeing the social proof (via likes, comments, follows) triggers the Bandwagon effect.

This is important to mitigate for social media products because without doing so, a few things can happen:

  • Existing influencers stop innovating and putting effort into content - since they’re almost guaranteed continued growth

  • New influencers stop coming to the platform because it gets harder and harder to break through without an existing following

Further reading: Rene Girard Mimetic Theory

👀 Mere-exposure effect

In the 1960s, psychologist Robert Zajonc ran a series of experiments where he showed participants various stimuli (some multiple times) and asked them to rate how much they liked them. He found that people rated stimuli they had seen before as more preferable.

Users prefer things that they are familiar with.

What does this mean for consumer social?

Use existing UI patterns, aesthetics, and language

Some people might think copying or cloning features from other products is uncreative and anticompetitive, but it’s actually highly rational. Products that use unfamiliar UI, color palettes, fonts, etc. are not only more difficult for users but users also perceive them as poorer quality.

  • If you’re building a camera app, the capture button is a circle and goes in the bottom center of the screen. See Snapchat.

  • If you’re building for Gen Z, use Gen Z color palettes and aesthetics. See Trash.

A great example of this is Twitter. In 2015, they changed from a star icon to a heart icon for like/favorite. Why? Virtually every other popular app was using the heart icon.

A great anti-example is the crypto space in general. I’ve said this many times before, but crypto adoption won’t happen so long as the industry chooses to use words like “governance” and user flows like Metamask. Conceptual backwards compatibility is required for any behavior change to happen.

Further Reading: Metaphors We Build By


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