Bookreview: “Hooked” From vitamins to painkillers. How do you form habits?

I read mainly business books, some of them are on techniques and methodologies, others are more focusing on soft skills. Most of the time, it’s hard to find a great book that is entertaining and not too long in that particular field.

Hooked is a must read in the list of product manager books. It’s a practical book, not theoretical. I guess to start the review I will put a quote from it which is important to every product manager.

“A habit is when not performing a behavior causes pain” tweet this

First there was an observation

As a product manager, most of my time I need to observe how user, sales, customer service, technical support or marketing interact and react to our product and releases. I have to observe them and understand what makes them delighted by our products.

It’s really hard to find what is called the “WOW” effect.

This effect is what every product manager is after I think.

My way to be recognize for my work is to know that users love what we are building and use it every time they need it.

This book explains to you how to reach that point. On a daily basis, I have to think about two things: the value and the way to hook the user to it
One can’t work without the other. You can build the best engagement in your product but if the value is not there, your product doesn’t worth a lot.

It needs to be your priority list

From a business point of view, it makes sense to hook your customer but when it comes to choose which feature to do, it becomes quickly intangible. 
Here is a list of the benefits defined by Nir Eyal:

“Higher customer lifetime value (CLTV), greater pricing flexibility, supercharged growth and a sharper competitive edge”tweet this

This book is a journey in itself, it explains the hook model and how Nir Eyal came with this idea. It is not just a model invented but something built from observation.

Each chapter is decomposed by an explanation more theoretical about the hook model and concrete example from brand such as Facebook, Pinterest, Twitter or Mint. 
At the end of each chapter, he wrote down some questions to remember as a product creator.

What is the hook model?

“Habits are not created, they are build upon.”tweet this

The hook model has 4 phases: Trigger, Action, Reward, Investment and it goes on.


A trigger can be internal or external. The ring of your phone is a perfect example of an external trigger. Missing someone or the curiosity to know what happens in the world is an internal one.

From a psychological point of view, internal triggers are way more powerful than external ones. 
As a product manager, I have to find out what motivates my users.


What is the simplest action a user can make in your product?

It can be logging in, it can be scrolling down (Pinterest), it can be searching (Google or Youtube). 
Analyzing the action from a user perspective is the best way to find out the simplest one.. 
Nir Eyal uses in this case the behavior formula from Fogg to explain to us what it matters in this action.

Formula is simple: 
Behavior = Motivation * Ability * Trigger

The more skilled a user become, the harder it should/can be from an ability point of view.

Motivation can be changed by six factors: seeking pleasure, hope or acceptance or in the opposite avoiding pain, fear or rejection.

The Ability can be affected by the time or money, by your physical condition, by the mental need it requires, by social conformity or originality, and finally if it’s routine or not.


The third phase of the model is the reward. It is based on three pillars: 
Tribe — Hunt — Self.

The Tribe rewards covers social rewards, partnership and recognition from others or a community. 
The Hunt rewards covers all the rewards materials or informational. It can be as simple as cash or finding the best tweets, best blogpost. 
The Self rewards covers all the intrinsic rewards. All the digital rewards you can find in games can be good examples (titles, new skills, upgrading your character)


Finally the fourth step is the Investment. The more the user invests time, effort, money, personal data or social connection the less he will risk to quit the application.

The investment can trigger the next of the loop.

On Instagram, posting your first picture doesn’t bring you much. Although collecting likes, will create a proud/good feeling about yourself. You start to invest time, material and you got the reward. It push you to start again, share more pictures and find ways to extend your network and gain more likes.

Final comments

Nyr Eyal studied and observed companies to write his book. He researched on the field to establish his methodology and you can find examples on how it works pretty easily. 
From a product manager perspective, thinking about how to hook your users is a prerequisite to do a good job. This book contains all the primary questions you should ask yourself on a daily basis. 
The only first step you need to do before defining the model, is to describe your primary users, your personas.

From a reader perspective

  • Review Amazon: 4.6 out of 5 stars on 72 reviews
  • Review GoodReads: 4.03 out of 5 stars on 6401 ratings and 511 reviews
  • Target: Product Manager, Startup, Brand manager

If you want to have a look at the presentation from Nir Eyal here it is. Available on slideshare.

Hooked Model from Nir Eyal

Have fun building your product and if you don’t like the rules just change them. There is no bad rules, there is just a bad interpretation of them.

A little click on the heart below will mean a lot to me.