> For the complete documentation index, see [llms.txt](https://www.designreference.xyz/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://www.designreference.xyz/cognitive-tools/ux-laws-principles/behaviour/hook-model.md).

# Hook Model

A four-step process (Trigger, Action, Reward, Investment) for building user habits.

The Hook Model is a cyclical process that businesses use to create habit-forming products. 

It begins with a trigger, an external prompt or internal cue that prompts a user to take action. This action, made simple and effortless by the product design, leads to a variable reward, a satisfying or surprising outcome that keeps the user engaged. 

The user then invests in the product, perhaps by creating content or connecting with others, deepening their engagement and making future returns more likely. This cycle repeats, with each iteration reinforcing the habit and drawing the user back to the product.

#### Further Reading

{% embed url="<https://www.productplan.com/glossary/hook-model/>" %}

{% embed url="<https://uxdesign.cc/what-budgeting-apps-fitness-trackers-and-duolingo-have-in-common-and-why-theyre-so-addictive-577bf6de5c0d>" %}


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