Summary Written by Jill Donahue
"This book provides cutting-edge science about how word of mouth and social transmission work. And how you can leverage them to make your products and ideas succeed."

- Contagious, page 27

The Big Idea

Word of mouth is persuasive

"Contagious products and ideas are like forest fires. They can’t happen without hundreds, if not thousands, of regular Joes and Janes passing the product or message along."- Contagious, page 206

Word of mouth is more effective than traditional advertising for two key reasons:

1) It is more trustworthy. Ads are not credible. We expect them to tell us how great the product is. Our friends, however, will tell us straight what they think about a product and so they are more believable.

2) It is more targeted. Companies create ads for a wide audience. Take an ad on the evening news for example. Only a portion of the viewers may need or be interested in the product. Word of mouth on the other hand is directed to an interested audience. I won’t share, for example, my enthusiasm about this book with everyone I meet. I will share it, however, with people who are either interested in growing their business or selling their product.

Insight #1

A checklist of 6 principals that drive things to catch on

"…certain characteristics make products more likely to be talked about and shared."- Contagious, page 207

Berger says that any product, idea, or behaviour can be contagious. Just build in some of the following principles (which he calls the six key STEPPS) by asking yourself the accompanying questions:

1. Social currency – There are three ways to leverage social currency:

  1. Find inner remarkability. Sharing extraordinary, novel or entertaining stories which make it more fun for people to talk about and also make them look good.
  2. Leverage game mechanics. The competition encourages social comparison. People care about hierarchy and will participate in things that help to show their status. Help them publicize their achievements to leverage this.
  3. Make people feel like insiders. If something is difficult to obtain, people assume it must be worth the effort. People will value it more and tell others to capitalize on the social currency of knowing or having it.

2. Triggers – What cues make people think about your product or idea? How can you connect it with something so it comes to mind more often? For example in 1997 the candy company Mars noticed an unexpected increase in sales of its Mars bar. Why? The well-publicized mission of NASA’s Pathfinder was to Mars! It triggered people to think of the Mars bar! What triggers people to think of your idea or product?

3. Emotion – Focus on feelings. What is the emotion connected to your product or idea? Ask yourself “why” three times, each time digging deeper.

4. Public – Can people see when others are using your product? How can you make the private public?

5. Practical Value – Does talking about your product or idea help others? How can you highlight value and package it into something others will want to disseminate so they can help the other person?

6. Stories – Is your product or idea embedded in a narrative that people will want to share? Is the story valuable?

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Insight #2

Top of mind means tip of tongue

"Triggers and cues lead people to talk, choose and use."- Contagious, page 92

There are great examples of each of the six principles above. As an example, let’s look at triggers. We think about and remember things that we are triggered to remember. You may forget to sign your daughter up for tennis lessons until you see some kids playing tennis in the park. Triggers impact your thinking all day long. If they are not there then they’re out of sight, out of mind. When I first started taking Omega 3 supplements I constantly forgot them, until I connected it with my placemat. When I sat down for dinner, my placemat wasn’t complete until it had an Omega 3 pill on it. The placemat acted as a trigger.

A study on this was done by Berger. His goal was to encourage students on campus to eat more fruits and vegetables. You might agree that most students know they should eat more fruits and vegetables and may even intend to eat more each day if reminded. But somehow, the fries and hamburgers make it onto the cafeteria tray instead. After measuring the baseline of actual consumption of fruits and vegetables, Berger exposed two groups to different slogans. The first group saw “Live the healthy way, eat five fruits and vegetables a day”. The second group saw “Each and every dining hall tray needs five fruits and vegetables a day.”

The slogans were similar except for one aspect. The second referred to the dining hall tray. Interestingly, the students rated that slogan as “corny” and scored it less than half as attractive as the first one. In fact, when asked if they thought the slogans would impact their behaviour they were more likely to say ‘no’ to the dining hall tray slogan. The results however of the study were striking. Students exposed to the first slogan did not change their behaviour whereas students exposed to the second, “tray” slogan markedly changed their behavior. Why? The trays triggered them to remember the slogan and they ate 25 percent more fruits and vegetables as a result. The trigger worked.

Berger suggests that products and ideas need “habitats” or places in which they live that have sets of triggers that cause people to think of them. How do you create triggers for the behaviour or product you want them to remember? For example, pairing Kit Kat and coffee in ads increased sales by a third! The ad made people think of Kit Kat when having their coffee. Remember Rebecca Black’s whiny song “Friday”? Were you as shocked as I was that such a poorly done song received such rapt attention? One of the factors may be that the title served as a trigger. When you analyze the search history for “Rebecca Black” on YouTube for March 2011, soon after it was released you will see a pattern of peaks on, you guessed it, every Friday! The trigger reminded people. Triggers are powerful.

What triggers can you associate with the behaviour you are trying to influence?

It’s encouraging to know that any product or idea can be contagious. Like a forest fire however, that spreads from one tree to the next, contagious products or ideas can’t happen without hundreds or thousands of users or believers who pass the product or idea along. Why do they pass them along? Certain characteristics make products and ideas more likely to be spread. Berger’s six principles help us increase that likelihood. How many can you include in your next product or idea you want to spread like wildfire? If you have a product or idea that was contagious, why was that? What principle had you used?

Read the book

Get Contagious on Amazon.

Jonah Berger

Jonah Berger is the James G. Campbell Assistant Professor of Marketing at the Wharton School at the University of Pennsylvania. He has published dozens of articles in top-tier academic journals, and popular accounts of his work have appeared in places like The New York Times, the Wall Street Journal, The Washington Post, Science, Harvard Business Review, Wired, BusinessWeek, and Fast Company. His research has also been featured in The New York Times Magazine’s annual “Year in Ideas” issue. Berger has been recognized with awards for both scholarship and teaching, including being named Wharton’s “Iron Prof.” At Wharton, he teaches an elective called Contagious: How Products, Behaviors, and Ideas Catch On. He lives in Philadelphia, Pennsylvania.

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