Hooked: How to Build Habit-Forming Products -My Scribbles

Jasmine Elamblakatt
5 min readJun 9, 2022

Hooked by Nir Eyal is no doubt one of the best book for Product Managers, Designers, Developers, Start-up founders and anyone who wanted to learn how to make their product a huge success by influencing people behavior. This book was one of the recommendation by my Manager.

We are all hooked to some behavior like checking news, tweets, or scrolling through YouTube, Instagram etc., this behavior is glued with us but we hardly notice. So here in this book writer talks about the technique to make habit forming products and how to get people addicted to the product in a good way.

Habits are automatic behavior which we do with little or no conscious thoughts. So to form this habits Hooked Model is used, The Hooked Model describes an experience designed to connect the user’s problem to a company’s product frequently enough to form a habit, its a simple yet powerful way to help customers form habits that connect their problem with the solution. The Hooked Model has four phases: trigger, action, variable reward, and investment.

1. Trigger:

Habits are formed over time, but the chain reaction that forms a habit always start with a trigger. Habits are not created, they are build upon, new habits need a foundation upon which to build. Triggers provide the basis for sustained behavior change. A trigger is the actuator of behavior which moves to take action. Triggers come in two types: external and internal.

External Trigger:

These triggers are embedded with information, which tells the user what to do next.

External trigger can be in any form like daily notification coming up, or can be through advertisements, search engine marketing, press mention, hot viral videos, featured app store placements, product referrals from friends or family or email newsletters etc. Some triggers drive new user acquisition while other trigger prompt repeat engagement until a habit is formed. Yet external trigger is the first step, the ultimate goal of it is to propel users into and through the Hooked Model.

Internal Trigger:

Unlike external triggers, we cant see, touch or hear an internal trigger. Internal triggers tells the user what to do next through associations stored in the user memory.

Internal trigger are created from user stored memory.

Human goes through lots of emotion, stress, pain, irritation or boredom in daily routines. To overcome these, different people use different techniques, like to kill boredom some people scroll through YouTube or news etc. Product owners must know the user internal trigger, and the pain they seek to solve. So the product that alleviates the pain and satisfies the user will form strong, positive association over time. After continued use, bond begins to form, and these bonds cement into a habit as users turn into your product when experiencing certain internal trigger.

New habits are sparked by external triggers, but associations with internal triggers are what keeps users hooked.

2. Action:

The trigger driver by internal or external cues, informs the user to perform the Action, but if the user does not take action, the trigger is useless.

There are 3 ingredients required to initiate any action : (a) the user must have sufficient motivation; (b)the user must have ability to complete the desired action; ( c) a trigger must be present to activate the behavior.

Example would be, suppose your phone rings and to pick it up(to perform Action) you require the motivation, suppose it can be a telemarketing call or you may not be in a good mood to answer; or the trigger to pick up the phone like the phone can be on silent mode; and the ability like the phone was buried in a bag and therefore difficult to reach. So like trigger, motivation and ability also play major role for initiating the Action.

There are different studies to predict or to increase the ability to perform an action

The Scarcity Effect describe how user value things when their is a scarcity in it, like in Online Shopping App the stock is displayed like “Only 2 left in Stock” this can influence buying behavior(action to be performed)

The Framing Effect describes how our mind takes shortcuts informed by our surroundings to make quick and sometimes erroneous judgments., like when same product with different price is kept we believe the one with high price is better.

The Anchoring Effect says that with only one piece of information user make a decision, like when shopping something, information like 30% off makes it attractive to take an action.

The Endowed Progress Effect , a phenomenon that increases motivation as people believe they are nearing a goal, like a progress showing only 20% left to finish, user is motivated to take further action and finish it.

3. Variable Reward:

The third step in the Hooked Model is the variable reward phase, in which user is rewarded for reinforcing their motivation for the action taken.

Understanding Variability:

Why variable Reward??

If something is received every time after an action then the trill in it is lost, but if a variability is added and the reward is given in random action then the probability of doing the action increases. Eventually the hunger to get the variable reward induces a habit of performing an action.

Facebook provides numerous examples of variable social rewards. Logging in reveals an endless stream of content friends have shared, comments from others, and running tallies of how many people have “liked ” something. The uncertainty of what users find each time creates the intrigue needed to pull them back again.

In case of Twitter, the variable rewards is in the form of relevant tweets, user scrolls and scrolls for a relevant content in which the tweets is filled with a mix of both mundane and relevant content.

4. Investment:

The more users invest time and effort into a product or service, the more they value it. In fact, there is ample evidence to suggest that our labor leads to love.

In this phase, users are asked to do a bit of work. Here users are prompted to put something of value into the system, which increases the likelihood of using the product. Investments are about the anticipation of long term rewards not immediate gratification.

Like in Twitter, user invest in putting valuable tweets to acquire and engage more followers. Investment can be in any form like in Twitter it can be followers or tweets added.

Investment differ from product to product like in some product investment can be as simple as adding item to favorites and in some product it can be building up the profile and followers.

Like in Pinterest, user invest on the site every time they pin an image of their own, repin someone else’s image, comment on, or like; these tiny investment help Pinterest to understand user taste and load next trigger.

Investment is the phase which brings the user back to the product and thus ending up creating a habit.

These are some of my highlights while reading the book, one must definitely read it for all the in-depth details and valuable information it holds.