The 10 Most Common Fallacies and Biases for Marketing Leaders

These are the fallacies and biases that plague all of us and are particularly trippy for marketing leaders.

They are the infamous “unknown unknowns,” which I am hoping — by virtue of this blog post — may now at least be known a bit better.

For a full list of fallacies and biases, I highly recommend the book The Art of Thinking Clearly. It’s been foundational for the customer research we do at Buffer and for the way we approach problems as clear-minded as possible (we think). Many of the fallacies below were pulled from the book.

Common fallacies and biases for marketing leaders

These are the pitfalls that I have noticed in myself, especially as I’ve gone deeper into my marketing career. I hope you may be able to recognize these fallacies, too, whenever they might crop up.

1. Survivorship Bias

What it is …

People overestimate their chances of success.

What it may look like … 

Being part of the “winning” team may cause you to identify success factors when none exist. You may have “won” because of coincidence.

Whenever we confuse selection factors with results, we fall prey to what Nicholas Taleb calls the swimmer’s body illusion. Without this illusion, half of advertising campaigns would not work.

Rolf Dobelli, The Art of Thinking Clearly

How to beware …

Guard against it by frequently visiting the graves of once-promising projects, investments, and careers. It is a sad walk but one that should clear your mind.

2. Sunk Cost Fallacy

What it is …

The more you invest in something, the harder it becomes to abandon it.

What it may look like …

What kinds of things are you doing today because it feels you’ve “come too far to give up now”?

A lot of marketing strategies remain in place because of the time, effort, money, and energy invested to get them up and running.

How to beware … 

Assess your investments from today forward. Be cautious in assigning value to what happened in the past. What’s done is done!

3. Consistency signifies credibility

What it is …

We assign credibility to things that remain constant and unchanging.

What it may look like …

If we decide to cancel a project halfway through, we create a contradiction: We admit that we once thought differently. Carrying on with a meaningless project delays this painful realization and keeps up appearances.

Rolf Dobelli, The Art of Thinking Clearly

How to beware …

Give yourself grace. People evolve, circumstances change, and the fact that you may be inconsistent from yesterday to today is not so much an indictment of your character as it is a commentary on your situation.

4. Confirmation bias

What it is …

We fit new information into our existing beliefs.

What it may look like …

We are unable to see things objectively. Whenever new information comes our way, we filter it through the lens of our existing theories, beliefs, and convictions. Put another way, we filter out the information that doesn’t fit with our views.

“Facts do not cease to exist because they are ignored.”

Aldous Huxley

See: the Internet.

We read the websites that fit with our view of the world, which can lead to misinformation, echo chambers, and groupthink.

How to beware …

Go outside your bubble for information. Know yourself better by taking unconscious bias training. Follow the social accounts of people who are different than you.

5. The contrast effect

What it is …

We judge something to be beautiful, expensive, or large if we have something ugly, cheap, or small in front of us. We have difficulty with absolute judgments.

Rolf Dobelli, The Art of Thinking Clearly

What it may look like …

Before / After testimonials are a classic example of this. To a degree, this thinking can seep into things like pricing tables as well.

pricing table example

How to beware …

When making a decision, try to assess each option individually.

6. Availability bias

What it is …

We form opinions based on the examples that most easily come to mind.

What it may look like …

For a common test of availability bias, try this test: Are there more words in the English language that start with “k” or have “k” as their third letter?

More than twice as many words have “k” as their third letter, but that’s not what people typically answer. It’s easier to think of examples where “k” is the first letter. Karate. Kaput. Kudos. But the third letter? … ack!

It is as if you were in a foreign city without a map, and then pulled out one for your hometown and simply used that. We prefer wrong information to no information.

Rolf Dobelli, The Art of Thinking Clearly

How to beware …

Be careful rushing an answer. Allow more time for big decisions so that you can rationally consider both sides — and perhaps take time to research and count “the Ks.” Spend time with people who are not like you so that you can broaden your context and knowledge.

7. Incentive super-response tendency

What it is …

People will act in their own best interest when given an incentive.

What it may look like …

“Never ask a barber if you need a haircut.”

If you goal your team around a particular outcome, the temptation will be to take the shortest route there. If your goal is followers, well, it’s easy to buy followers. If your goal is traffic, well, it’s easy to build a bot.

There’s also this classic example from 1947: Soon after the Dead Sea Scrolls were discovered, archaeologists set a money reward for each new Dead See Scroll artifact that someone could find. When someone did find a scroll, they tore it into pieces to claim multiple rewards.

How to beware …

Be careful how you set goals and incentives for your team. There’s a great post by John Egan of Pinterest about setting goals for growth teams. Here’s a snippet:

Growth teams are hyper metric focused and even with the best intentions, they can sometimes over optimize for a metric. To counteract this, you want to ensure that metrics cannot easily be “gamed” and that they are tied to the long-term success of the company. You can do this by going deeper than the surface level metrics and setting goals based on down funnel engagement.

John Egan, Pinterest

8. Illusion of control

What it is …

Every day, shortly before nine o’clock, a man with a red hat stands in a square and begins to wave his cap around wildly. After five minutes, he disappears. One day, a policeman comes up to him and asks: “What are you doing?”

“I’m keeping the giraffes away.”

“But there aren’t any giraffes here.”

“Well, I must be doing a good job, then.”

What it may look like …

We may think we have control of certain outcomes in marketing: campaign reach, funnel optimizations, branding. And yes, we can quantify these to a certain extent. There’s also a whole world of levers we may not know about at first.

How to beware …

Be quick to learn.

Know that you can’t understand fully how something works, much less control its outcome. Learn fast as you receive new inputs; you’ll quickly see what you can control and what you can’t.

9. Outcome bias

What it is …

We evaluate decisions based on the result of the decision, not the decision-making process.

What it may look like …

Have you ever heard a gambling hotline guarantee that they can pick winners with 100% accuracy?

Well, they can! Sort of.

Let’s say 1,000 people call in to take the gambling pro up on the offer. For the first game, the pro chooses one team for 500 people and the other team for the 500 remaining callers. After the game, 500 people think the gambling pro is 100% right. The pro does it again for the next game, splitting the picks. After the game, 250 people think the pro is a genius. This can go on a very long time! Ten games in, there are still two people who believe this pro is right 100% of the time.

Should word get out about this gambling pro, people will want to know how he does it, and they’ll look for any best practices to follow. They might find some; perhaps commonalities exist among the correct picks. But ultimately, what was the decision-making process behind the genius? Randomness and math.

How to beware …

Especially in marketing we are inundated with “How we grew this thing by this percent!” blog posts and surrounded with influencers who boast of incredible successes. While enjoying these articles and learning from these folks, also keep in mind what it took to achieve the results. Really get to know the process and all the factors involved before you rush to praise.

10. Liking bias

What it is …

According to research, we see people as pleasant, if (a) they are outwardly attractive, (b) they are similar to us in terms of origin, personality, or interests, and c) they like us.

What it may look like …

This is one of the factors behind social proof. Brands want to capture quality “logos” to put on their home pages; ideally, these logos attract more of the same types of logos.

You also see this a lot with how marketing chooses the people for its campaigns or the photos and assets for its social profiles. To make a brand seem pleasant and appealing to a target audience, the imagery and design reflects attractiveness, the people are approachable, and the brand itself is responsive and caring in its interactions.

(This is especially interesting to consider with diversity and inclusion. To what degree can anyone identify with your brand? Or are you basing your visuals on certain types of people only?)

How to beware …

When you find yourself attracted to a brand or a person, run a quick check to see how much of it might relate to this liking bias. Are there things you enjoy about this brand/person beyond the factors of the liking bias?


Over to you

I’d love to hear what biases you’ve identified in your job or in your day-to-day. Come find me on Twitter!


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