The Why #54: Why do we follow terrible trends?

4 min readNov 10, 2022

By Dan Monheit, 11.11.22

Here’s the thing, Matilda. Every man arrives at an age where they decide that this is the look I will die with. For me, it happened somewhere between 2013 and 2016. Skinny jeans. Sneakers. Black tees. I’m done.

Everyone else though? Yes they absolutely do follow terrible trends. Not a moment after finally throwing out my last pair of baggy jeans, cargo pants and baggy cargo jean pants, they seem to have miraculously appeared on every person under the age of 25. Honestly, the youth of today…

If it’s not baggy jeans, it’s UGG clogs (gah!), platform sandals (gah!) or the revival of Y2K bedazzling (I think we can all still get around this one). While every one of these sounds ridiculous in its own right, it seems that once the trend starts taking off, no amount of objective reasoning can slow it down.

So why do we do it to ourselves? What makes us toss out the perfectly good ‘old’ to fit in with the questionable (and usually down right ugly) ‘new’? Well Tilly, when it comes to trends, this middle aged dad has got you covered…

Social Proof

Refers to our innate herd mentality. When we see a group of people acting in a certain way, we tend to automatically believe that that must be the correct, appropriate, desirable thing to do — especially if we’re in a situation that’s unfamiliar or risky.

One of the most famous examples of Social Proof in action comes from the UK’s Behavioural Insights Team (aka the Nudge Unit). This specialised part of the UK government was tasked with encouraging more people to pay their taxes on time. 100,000 late-tax-paying citizens were randomly divided into groups, with each group receiving a different letter.

One group’s letter was a simple, standard reminder that the recipient’s taxes were due.

A second group’s letter focused on threats and penalties for not complying.

A third group’s letter talked about the recipient’s civic duty and the importance of taxes for funding schools, parks, hospitals and roads.

Interestingly, none of these letters performed anywhere near as well as the letter that informed recipients that the majority, in fact 90% of people in their category, had already paid their taxes and that they were, in fact, an outlier. Recipients of these letters were at least 15% more likely to comply, which led directly to almost $10m in additional collections in the first 23 days alone!

As it happens, there are actually three certainties in life: death, taxes, and the power of Social Proof.

So back to why you’re now shopping for a $1,400 Diesel belt that’s actually just a giant piece of velcroed plastic.

We’re simple creatures. For the vast majority of human history, being separated from the group meant almost certain death, so it makes sense we’re wired to stick with the group, no matter how ridiculous the group might look.

For brands, tapping into our herd mentality can make all the difference. Showing prospective customers that people who are ‘just like them’ have already done the thing we’re asking them to do can be more motivating than we’d ever anticipate. Yes, even when it comes to something as uncomfortable, but undeniably cool, as the 2014 skinny jean.

Behaviourally Yours,

Dan Monheit

PS If you missed the last edition, you can still check out why you always want something sweet after a healthy meal here.

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Bad Decisions Podcast
Learn more about Social Proof in episode 5 of the Bad Decisions podcast.

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Check out Dan’s write up in Smart Company on how Liquid Death broke all the rules in the wellness sector to deliver a marketing masterstroke here.




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