Welcome back to 52 Weeks of Marketing Wisdom, where we review and recommend a new book weekly across five themes: Foresight, Customer, Strategy, Creativity & Innovation, plus two extras to complete the 52.

Our program is for busy marketing professionals seeking inspiration and growth through reading.

Rather than a simple review, we've evolved our blog posts to bring a point of view to the work and focus on how it informs what we do at Selbey Labs.

We are currently looking at the theme of Strategy and this week, we're inspired by the wonderful book Contagious, which looks at how ideas go viral, by Jonah Berger. 

This is our last post before the holidays and we will pick up again in January.

Hope you enjoy it.

Why Some Ideas Catch Fire (And Why Marketers Need to Care)

Here’s the truth: most ideas go nowhere.

You put out a campaign, a product, or a post. You think it’s clever, creative, even brilliant. And then? Silence.

Meanwhile, someone else posts a video of a cat playing the piano, and the internet explodes. Millions of views, shares, and comments. People are talking about it at work, in WhatsApp groups, and over dinner. It’s viral.

Why does this happen? Why do some ideas, products, or campaigns catch fire while others fizzle out?

Jonah Berger’s Contagious: How to Build Word of Mouth in the Digital Age has the answer. He’s spent years studying why people share certain things and ignore others. His research boils down to this: it’s not luck. It’s science.

For marketers, understanding this science isn’t optional. It’s the difference between a campaign that drives sales and one that’s dead on arrival.

It’s Not About Going Viral

Let’s get one thing straight. Berger isn’t just talking about viral videos or internet memes. Sure, we all love a good Ice Bucket Challenge, but most word of mouth happens offline—face to face, over coffee, or in a meeting.

According to Berger, 20 to 50% of all purchasing decisions are driven by word of mouth. That’s massive. It’s also free. No ad spend. No media buys. Just people talking to other people.

The question is: how do you get them to talk about you?

Berger’s research gives us the answer: the **STEPPS framework.

Why Things Spread: The STEPPS Framework

Berger breaks it down into six principles. These aren’t random tricks—they’re the psychological and social triggers that make people share.

1. Social Currency: People share things that make them look good. Think about Please Don’t Tell (PDT), a hidden cocktail bar in New York. To get in, you enter a phone booth and dial a secret number. People share this because it makes them look cool, like insiders who know something exclusive.

The lesson? If your product or campaign makes people feel special or in-the-know, they’ll talk about it.

2. Triggers: Top of mind, tip of tongue. People share what’s right in front of them. Kit Kat boosted sales by linking itself to coffee: “Kit Kat and coffee—a break’s best friend.” Every time someone had coffee, they thought of Kit Kat.

The lesson? Link your product to everyday moments or habits, and it’ll stay top of mind.

3. Emotion: When we care, we share. But not all emotions are created equal. Berger explains that high-arousal emotions like awe, anger, or excitement drive more sharing than low-energy feelings like sadness.

Dove’s “Real Beauty” campaign is a perfect example. It evoked awe and self-reflection, making millions of people share it.

The lesson? Don’t just inform people—make them feel something.

4. Public: If it’s built to show, it’s built to grow. Apple understood this when it launched the iPod with those iconic white earbuds. Suddenly, anyone walking down the street with white earbuds became a walking billboard for Apple.

The lesson? Make your product or idea visible. If people can see it, they’ll imitate it.

5. Practical Value: People love to share useful things. Life hacks, “10 tips to save money,” or a video showing you how to use a blender to crush an iPhone (shoutout to Blendtec’s “Will It Blend?” campaign) all fit the bill.

 The lesson? Show people how your product makes their lives easier or better, and they’ll pass it on.

6. Stories: Facts are forgettable, but stories stick. Subway didn’t just tell people its sandwiches were healthy—it shared Jared’s story of losing 200 pounds by eating them. People didn’t just remember it—they retold it.

The lesson? Wrap your message in a story, and it’ll travel further.

Why Marketers Need This Framework

Here’s where most marketers go wrong: they focus on their message but forget the mechanics of sharing. They spend millions on a campaign and assume people will care.

Berger flips the script. He shows that it’s not about shouting louder—it’s about giving people something worth talking about.

This is especially critical in today’s world. Attention is fragmented. People scroll past a thousand ads every day. You can’t buy their attention—you have to earn it. And the best way to do that is by understanding what makes them share.

The Power of Word of Mouth

Berger’s big point is this: "word of mouth is more powerful than traditional advertising." It’s more credible because it comes from someone you trust. It’s more targeted because people only share with others who’ll care. And it’s self-perpetuating—one conversation leads to another, then another.

But word of mouth doesn’t just happen. You have to engineer it. That’s where the STEPPS framework comes in. By building campaigns and products that tap into these triggers, you can make your ideas contagious.

What This Means for You

If you’re a marketer, this book is your playbook. It’s not about throwing money at ads or praying for a viral hit. It’s about understanding the psychology of sharing and designing campaigns that spread naturally.

So, the next time you’re working on a campaign, don’t just ask, “What do we want to say?” Ask, “Why would someone share this?”

Because as Berger puts it: “It’s not about pushing people to talk—it’s about giving them something worth talking about.”

If you want your ideas, products, or campaigns to catch fire, you need to read Contagious. It’s not magic. It’s science. And it works.

If you would like your brand to be more contagious, visit us at www.selbeyanderson.com

Contagious, How to Build Word Of Mouth In The Digital Age, Jonah Berger