Nir Eyal in his book ‘Hooked’ has talked about behavioral design in order to help manufacturers create products that generate habit-forming behaviors in users. Within this context, the author has put forward the Hook Model which is compromised by four steps:

1. Trigger

The first step of the model is the trigger which leads to a behavior, and can either be internal or external. For instance, when it comes to social media platforms like Facebook and Instagram, users are triggered to sign up for an account in order to look into existing social material available online.

External triggers are the visible call-to-actions a user may come in contact with, ranging from an email to a website link. This trigger will, in turn, lead the user to an action or behavior. Then, as users start to shape particular associations, internal triggers come into play. Users start to associate actions with behaviors and emotions. This process is repeated until a habit is being formed.

2. Action

The second step of the Hook model is action and here the role of business is to make the life of the user as easy as possible. The user should experience a seamless procedure that is easy to use, induces no problems, and boosts the user’s motivational to reach the desired action. This step is all about product design and user experience.

3. Variable Reward

Following, the next phase embodies the variable reward that needs to be given out to the user once the action is completed. The author highlights the need for variability in order to arouse the user’s interest and motivate him to move further. This might range from a tangible reward to an exciting piece of information.

4. Continued Investment

Finally, the last step of the Hook model is investment and is the point at which the user fives something back to the product or service. This might be time, money, data or just effort. For instance, an investment may occur when students leave feedback subsequent to a course, or when users share an invite link with their friends to download the app. If you manage to motivate users to invest in your product, then it means that they value and support your idea.

It is important to note that the Hook model is a circular process that never ends. Having reached the final step of the model; the investment phase, the process starts all over again. This is how habit-forming behaviors are created in users and how gadgets become so addictive. It’s all about crafting emotional connections between brands and customers through the perspective of psychological marketing.


The Hook Model of Behavioral Design may be applied to a broad spectrum of scenarios, such as in the field of education. By creating an interactive, user-friendly learning application that meets all the above phases of the Hook model, students will start to enjoy learning and a habit-forming behavior will be eventually be formed. Here, seamless user experience and built-in rewards are key areas to note.