Hooked: How to Build Habit-Forming Products

“As companies combine their increased connectivity to consumers, with the ability to collect, mine, and process customer data at faster speeds, we are faced with a future where everything becomes potentially more habit forming […] building habit-forming products is indeed a superpower. If used irresponsibly, bad habits can quickly degenerate into mindless, zombielike addictions.” 

Eyal discusses Habit Formation, Addiction, and Ethics. He connects the abilities of companies to gather data about their users with the potential for making habit-forming products that entice customers to return routinely. While Eyal’s work teaches people to do just this, he concedes that there are ethical limitations and that designers should not aim to ensnare their users into “zombielike addictions.”

“Altering behavior requires not only an understanding of how to persuade people to act—for example, the first time they land on a web page—but also necessitates getting them to repeat behaviors for long periods, ideally for the rest of their lives.”

Eyal explains that, in order to be successful, companies must not merely persuade users to navigate to their site or make a single purchase; they must be Turning Conscious Decisions Into Subconscious Behavior. In other words, the company must focus on building their products into people’s routines. This will increase the chances that their users form habits around using products, thus increasing company profits.

“A company can begin to determine its product’s habit-forming potential by plotting two factors: frequency (how often the behavior occurs) and perceived utility (how useful and rewarding the behavior is in the user’s mind over alternative solutions).”

In Chapter 1, Eyal describes the two factors which inform how likely a user is to form a habit around a product. Frequency, he says, is essential in forming habits; even very useful actions may never become habits if they are not repeated often enough. This passage reveals some of the limitations around creating habit-forming products, since companies which sell items or services that people need infrequently will likely fail to create habits and routines around their products.

“Addictions, by definition, are self-destructive. Thus it is irresponsible to make products that rely on creating and maintaining user addictions because doing so would mean intentionally harming people. A habit, on the other hand, is a behavior that can have a positive influence on a person’s life.”

Eyal distinguishes between addictions and habits, claiming that addictions are inherently destructive while habits might be positive or negative. He suggests that his methods for making products more habit forming are not unethical, noting that some habits have a positive effect on people’s lives. Eyal does not explore how some habits may progress into addictions, or how tech designers can distinguish between whether they have created an addiction in a user or merely encouraged a habit.

“More choices require the user to evaluate multiple options. Too many choices or irrelevant options can cause hesitation, confusion, or worse—abandonment. Reducing the thinking required to take the next action increases the likelihood of the desired behavior occurring unconsciously.”

Eyal explains that external triggers function best when they are very clear and simple. The less conscious deliberating the user must do, the more likely they are to follow through with action and engagement. This quotation emphasizes the connection between appealing triggers and users’ habitual, automatic responses.

“Yet external triggers are only the first step. The ultimate goal of all external triggers is to propel users into and through the Hook Model so that, after successive cycles, they do not need further prompting from external triggers. When users form habits, they are cued by a different kind of trigger: internal ones.”

Eyal again explores Turning Conscious Decisions Into Subconscious Behavior. He explains how external triggers such as company newsletters, website links, or ads are most effective if they prompt the user to use a site or app, experience its rewards, and invest value such as time, data, or money. These experiences subconsciously incentivize the user to repeat this experience again in the future, cementing it into a habit.

“Sites such as LinkedIn and Facebook utilize this heuristic to encourage people to divulge more information about themselves when completing their online profiles. On LinkedIn every user starts with some semblance of progress […] The next step is to ‘Improve Your Profile Strength’ by supplying additional information. As users complete each step, the meter incrementally shows the user is advancing.”

Eyal argues that the “endowed progress effect” can entice people to engage more deeply with a product and satisfy the “action” step in his Hook Model. The “endowed progress effect” makes people feel incentivized to complete some kind of goal, for instance, increasing their “profile strength” on LinkedIn. This is one way that companies entice people to invest more time and data in their products. 

“Every behavior is driven by one of three Core Motivators: seeking pleasure and avoiding pain; seeking hope and avoiding fear; seeking social acceptance while avoiding social rejection.”

Eyal claims that any action people take in their lives—including their digital behavior—is subconsciously prompted by three instinctual motivators. By rewarding at least one of these, designers can entice users to see their products as a way to gain pleasure, reassurance, or social acceptance, and therefore use it more frequently. Here, Eyal develops his theme about the relationship between Psychology and Successful Product Design.

“You do not have to be a hard-core video gamer to be heavily influenced by gamelike experiences. The humble email system provides an example of how the search for mastery, completion, and competence moves users to habitual and sometimes mindless actions. Have you ever caught yourself checking your email for no particular reason?”

Eyal argues that the psychological impulses that drive people’s online behaviors do not only apply to more obviously addictive platforms, such as gaming, but can include everyday messaging. He singles out email systems as appealing to all three variable reward systems: the hunt, the tribe, and the self. He challenges the reader to consider their own online behavior and if any of them have progressed into subconscious habits.

“The magic words the researchers discovered? The phrase ‘But you are free to accept or refuse.’ The ‘but you are free’ technique demonstrates how we are more likely to be persuaded to give when our ability to choose is reaffirmed.” 

Eyal explains that simply reminding a user of their autonomy can be a persuasive tactic, as people like to feel that they are free and in control of their choices. This tactic decreases “reactance,” where the desire to resist being oppressed or controlled may cause one to lose trust in a person or product. Eyal suggests his claims are based in scientific evidence, as he refers to several studies which demonstrate this phenomenon.

“Fundamentally, variable reward systems must satisfy users’ needs while leaving them wanting to reengage. As described, the most habit-forming products and services utilize one or more of the three variable reward types: the tribe, the hunt, and the self. In fact, many habit-forming products offer multiple variable rewards.”

Eyal explains that different companies must consider what their users would find most rewarding, and include at least one type of variable reward with their product. He reminds the reader that these rewards may be social, such as connecting with others or earning their approval, or more material, such as finding good information or earning a resource. Rewards could also be more catered to individuals by creating a sense of completion or accomplishment.

“Together, the three tendencies just described influenced our future actions: The more effort we put into something, the more likely we are to value it; we are more likely to be consistent with our past behaviors; and finally, we change our preferences to avoid cognitive dissonance.”

Eyal explores how to coax users to invest in using a product. According to Eyal, the “Investment” step is crucial to incentivizing further engagement; humans are proven to value things more if they have helped to build it in some way, and tend to continue behaviors they have engaged in the past.

“When players contemplate making a purchase, they acknowledge it is unwise to spend money on something that is not good. Yet just like the fox that perceives the grapes as sour to reduce his frustration at not being able to reach them, players justify their purchases to help convince themselves of something they want to be true, namely, that they are not foolish. The only solution is to keep paying to keep playing.”

Eyal uses a simile, where something is compared to something else using “like” or “as.” In this case, he compares modern consumers to the fox in Aesop’s fable, who changes his perception of a bunch of grapes so he does not have to feel incompetent. Eyal explains that users also exhibit this form of denial when they refuse to admit that they have wasted time or money on a product.

“The study found that the group given helpful computers performed almost twice as much work for their machines. The results showed that reciprocation is not just a characteristic expressed between people, but also a trait observed when humans interact with machines […] As it turns out, we invest in products and services for the same reason we put effort into our relationships. 

Eyal claims that companies do not need to make their products as easy to use as possible, since people naturally expect to put a bit of work into a product to make it better or more personalized. By asking users to invest a small amount of effort into the product after receiving a “reward” from it, companies can harness human psychology for their own benefit.

“For many users, switching services means abandoning years of investment and starting over. No one wants to rebuild a loyal following they have worked hard to acquire and nurture.”

Eyal describes how simply following others and gaining friends or followers on social media constitutes an investment of time and effort, one which may help the user gain social or monetary rewards. By making this investment, the user is incentivized to stay on that particular social media platform. 

“Pinterest clearly demonstrates the four stages of the Hook Model. It is a seamless flow: from the itch of the internal trigger that moves users to the intended action, through the variable reward, and finally to the investment, which also loads the next external trigger.”

Eyal points to Pinterest as a site which has perfected his “Hook Model.” He provides an example of this model for both industry professionals and everyday readers who have likely used Pinterest before.

“Investments in a product create preferences because of our tendency to overvalue our work, be consistent with past behaviors, and avoid cognitive dissonance. Investment comes after the variable reward phase when users are primed to reciprocate.”

Eyal summarizes why making “investments” in a product tends to encourage people to use it again in the future. He explains the psychological traits that prompt users to put work into using products, and when to ask the user for such an investment.

“Perhaps while reading this book you asked yourself if the Hook Model is a recipe for manipulation. Maybe you felt a bit unsettled reading what seemed like a cookbook for mind control. If so, that is a very good thing. The Hook Model is fundamentally about changing people’s behaviors, but the power to build persuasive products should be used with caution.”

Eyal again explores Habit Formation, Addiction, and Ethics. He encourages the reader to feel “unsettled” about how the Hook Model could be used inappropriately to encourage behavioral changes that do not benefit the user. He claims that his work should be used to make genuinely helpful products that enrich people’s lives.

“The Matrix seeks to help you answer not ‘Can I hook my users?’ but instead ‘Should I attempt to?’ To use the Manipulation Matrix, the maker needs to ask two questions. First, ‘Would I use the product myself?’ and second, ‘Will the product help users materially improve their lives?’"

Eyal argues that persuasive design is only ethical if it passes his Manipulation Matrix questions. This passage shows that Eyal is aware of how his knowledge could be used for unethical purposes. Here, he explains how he does not support any company or product using these strategies in negative ways. For readers in the tech industry, this quotation is a direct challenge to consider the morality of the products they are designing.

“When you create something you would use, that you believe would make the user’s life better, you are facilitating a healthy habit. It is important to note that only you can decide if you would actually use the product or service, and what ‘materially improving the life of the user’ really means in light of what you are creating.”

Eyal asks the reader to seriously consider how their product could improve the user’s life. Without any kind of use or enrichment, forming a habit around a product could prove detrimental to the user. Eyal acknowledges that this method requires product designers to police themselves, and hints at the subjectivity of the process. A potential critique of Eyal’s approach is that designers may want the user to benefit in a certain way, without being able to control the user’s whole experience of a product.

“Creating a product that the designer does not believe improves users’ lives and that he himself would not use is called exploitation […] Casinos and drug dealers offer users a good time, but when the addiction takes hold, the fun stops.”

Eyal urges the reader to not emulate the “dealer” kind of designer who seeks to profit from people’s addiction to products that actively harm them. By pointing to casino owners and drug dealers as examples of the “dealer,” Eyal creates a stigma around this approach to design and business. This quotation prompts the reader to consider which category of professional they belong to and how their product may hook users, for better or for worse.

“Gruenewald says his Bible App also offers an element of mystery and variability. ‘One woman would stay up until just past midnight to know what verse she had received for her next day,’ Gruenewald says. The unknown—in this case, which verse will be chosen for the reader and how it relates to their personal struggle—becomes an important driver of the reading habit.”

Eyal explains that even receiving daily notifications can constitute a kind of digital reward. For instance, users who appreciate daily Bible verses enjoy receiving a verse each day for them to reflect on. This expectation increases their engagement with the service. It encourages them to integrate the product into their daily routine, since updates are sent at regular times each day.

“The Bible App increases users’ ability to take action by front-loading interesting content and providing an alternative audio version. By separating the verses into small chunks, users find the Bible easier to read on a daily basis; not knowing what the next verse will be adds a variable reward. Every annotation, bookmark, and highlight stores data (and value) in the app, further committing users.”

Eyal explains how the Bible app successfully prompts users through each stage of the Hook Model, with great success. He reminds the reader how designers can make their products persuasive and habit forming. By using the example of an online Bible, an already ubiquitous text, Eyal emphasizes that nearly any kind of resource can be made into a habit-forming product with the right design.