Contagious: Why Things Catch On

Contagious: Why Things Catch On

by Jonah Berger

Contagious provides research-based principles for determining what causes things to spread. It outlines the six distinct characteristics that determine whether a product, idea, or behavior pervades culture or fails to see the light of day. These principles, abbreviated "STEPPS," demonstrate that for a product or idea to be talked about and succeed, it must provide social currency, have environmental triggers, evoke emotion, be public, provide practical value, and be wrapped in a story. The book challenges us to look for these characteristics in our own products and ideas and leverage them to achieve market dominance.

Summary Notes

The Best Form of Advertising

“Word of mouth is the primary factor behind 20 to 50 percent of all purchasing decisions.”

There are many examples of things that caught on — non-fat Greek yogurt, the six sigma management strategy, smoking bans, and a low-fat diet. While these examples abound, it’s hard actually to get something to catch on.

Even with all the money poured into marketing and advertising, only a few products have become popular. Most restaurants bomb, most businesses go under, and most social movements fail to gain traction. So why do some products, ideas, and behaviors succeed when others don’t?

Social influence and word of mouth play an important role here. As we all know, people love to share stories, news, and information with those around them. We tell our friends about great vacation spots, chat with our neighbors about good deals, gossip with coworkers about coming layoffs, write online reviews about movies, and tweet about recipes we just tried. 

The best thing about word of mouth is that it’s available to everyone and doesn’t require spending millions of dollars on advertising. It just needs getting people to talk. Harnessing the power of word of mouth requires understanding why people talk and why some things get talked about more than others. Regardless of how plain or boring a product may seem, there are ways to make it contagious.

Actions to take

We Share Things That Make Us Look Good

“So, not surprisingly, people prefer sharing things that make them seem entertaining rather than boring, clever rather than dumb, and hip rather than dull.”

Think about the last time someone shared a secret with you. If you’re like most people, you probably went and told someone else. Secrets rarely remain secret for long because once people know it's a secret, they're more likely to talk about it. This is because of social currency.  People tend to share things that make them look good to others.

Now, consider the flip side. Think about the last time you considered sharing something but didn’t. Chances are you didn’t talk about it because it’d have made you, or someone else, look bad. We talk about how we got a reservation at the hottest restaurant but skip the story about how the hotel we chose faced a parking lot.

Just like people use the money to buy products or services, they use social currency to buy positive impressions among members of their circle. So, to get people talking about your product, service, or idea, you need to mint social currency. Give them a way to make themselves look good while promoting it to others.

Actions to take

Top of Mind, Tip of Tongue

“By acting as reminders, triggers not only get people talking, they keep them talking. Top of mind means the tip of the tongue.”

Imagine you’ve just gotten an email about a new recycling initiative. Chances are you’ll talk about it with your coworkers later in the day or mention it to your spouse that weekend. But how likely is it that you’ll mention it again to someone else months later?

At any given moment, some thoughts are top of mind or more accessible than others. Right now, you might be thinking about the sentence you’re reading or the sandwich you had for lunch. But stimuli in your surrounding environment can also determine which thoughts are top of mind for you. If you see a puppy while jogging, you might remember that you’ve always wanted to adopt a dog. If you smell Chinese food while walking past the corner noodle shop, you might start thinking about what to order for lunch.

What we see, smell, and hear can trigger related thoughts and ideas, placing them on top of our minds all too often. This matters because accessible thoughts and ideas lead to action. So, when advertising, rather than going for a catchy message, consider the context. Think about whether the message will be triggered by the everyday environments of your target audience. Remember that a strong trigger can be much more effective than a catchy slogan.

Actions to take

When We Care, We Share

“Emotion sharing is thus a bit like social glue, maintaining and strengthening relationships. Even if we’re not in the same place, the fact that we both feel the same way bonds us together.”

For something to go viral, many people must pass along the same piece of content at around the same time. This means a large number of people had to make the same decision. A big driver of that decision is emotion, which deepens the social connection between those who share and their recipients. 

If you send a coworker a joke that cracks both of you up, it underscores your connection. If you send your cousin an op-ed piece that makes you both angry, it strengthens the fact that you share the same views.

Both positive and negative content evoke emotions that make us want to share them with others, and we’re more likely to follow through with sharing when the emotions are high-arousal. Anger and anxiety are examples of negative but high-arousal emotions, while excitement, awe, and amusement are examples of positive, high-arousal ones.

Low-arousal emotions like sadness, on the other hand, decrease sharing. Contentment has the same effect. While it’s a pretty good feeling, people are less likely to share or talk about things that make them content because contentment decreases arousal.

Actions to take

Built to Show, Built to Grow

“Making something more observable makes it easier to imitate. Thus a key factor in driving products to catch on is public visibility. If something is built to show, it’s built to grow.”

We often imitate those around us. We dress in the same styles as our friends, pick entrees preferred by other diners, and reuse hotel towels more when we think others are doing the same. We assume that if other people are doing something, then it must be a good idea to do it too. After all, they probably know something we don’t.

The famous phrase “Monkey see, monkey do” captures more than just the human penchant for imitation. People can only imitate what they see others doing. A college student may personally be against binge drinking but still do so because that’s what they see others doing. A restaurant might be extremely popular, but if it’s hard to see inside, passersby looking to eat may shun it as empty and thus not in demand.

Observability has a huge impact on whether products and ideas catch on. Similar shirts and blouses sell more widely than similar socks because shirts are public and socks are private. Approximately one out of every eight cars sold is due to social influence. We may not notice it, but observable things are more likely to be discussed as well. 

The easier something is to see, the more people talk about it. And the more they talk about it, the more likely they will act on it.

Actions to take

News You Can Use

“People share practically valuable information to help others. Whether by saving a friend time or ensuring a colleague saves a couple of bucks next time he goes to the supermarket, useful information helps.”

People like to pass along practical, useful information that can also benefit others. They don’t just value it; they share it. At its core, sharing a practical value is about helping others, encouraging them to do what they should do in a faster, better, and easier manner. 

We go out of our way to give advice or send others information that’ll make them better off. Think about the last time you made a decision that required you to gather and sift through large amounts of information. You probably asked one or more people what you should do, and they either shared their opinion or sent you a link to a website that helped.

Finding practical value isn’t hard. Almost every product or idea imaginable has something useful about it—whether it saves people money, makes them happier, improves their health, or saves them time. If you share news that people can use, it will make them appreciate you and your product more and share that appreciation with others. 

Simply thinking about why people would want to gravitate to your product or idea in the first place will give you a good sense of the practical value it can and should offer.

Actions to take

Information Travels Under the Guise of Idle Chatter

“... That’s because people don’t think in terms of information. They think in terms of narratives. But while people focus on the story itself, information comes along for the ride.”

Narratives are inherently more engaging than basic facts. If people get sucked in early, they’ll stay for the conclusion. Think about it: How often did you hang on to every word whenever someone told you a good story? Chances are you do it all the time. 

You want to find out whether they missed the flight or what they did with a house full of screaming nine-year-olds. You started down a path, and you want to know how it ends. Until it does, they’ve captured your attention.

Stories carry things — a lesson or moral, information, or a take-home message. Lessons or morals are embedded in fairytales, fables, and urban legends. You may have heard about the story of “The Boy Who Cried Wolf,” which warns about the dangers of lying. You may have also known the story of “Cinderella,” which shows that being good to others pays off in the end. 

Even the ordinary stories we tell one another every day also carry information. They provide a quick and easy way for people to acquire lots of knowledge vividly and engagingly. One good story about a mechanic who fixed the problem without charging is worth dozens of observations and years of trial and error. Stories save time and hassle and give people the information they need in a way that’s easy to remember.

People are also less likely to argue against stories than against advertising claims. First, it’s hard to disagree with a specific thing that happened to a specific person. Second, we’re so caught up in the drama of what happened to the person that we don’t have the cognitive resources and energy to question what’s being said. So, in the end, we’re more likely to be persuaded.

Actions to take

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