Hook Model Step 4: Investment

In this part of the model, the user is asked to do a little bit of work. This is the phase where: 1. the odds where the user will make another pass through the hook model will increase, and 2. the user's brain is swimming in dopamine so the company is now letting up pay for that dopamine.

The investment generally varies between giving a combination of time, data, effort, social capital, or even money. 

However, the investment phase implies that this action that the user is willing to do will improve the service for the next go-around.