Make your users make an investment in your product.

Investment is the fourth element of the hook model. It’s an important part of increasing engagement with your product. The investment phase is about anticipation of the rewards in the future. Investment increases the likelihood the user will return.

If you start with small investments that users will put into your product, over time they will build a very strong connection to it.

Understand these three tendencies that influence our future actions:

1. The more effort we put into something, the more likely we are to value it.
   For example, we value the furniture from Ikea more because we assembled it.

2. We are more likely to be consistent with our past behaviors.
   If we ask a user to do a small thing, they will be much more likely to do something bigger, in order to be consistent with their past actions.

3. We change our preferences to avoid cognitive dissonance.
   We adopt to the situation in order to feel better about things.

Next, make your product in such a way that users will have to put some investment into it. Good examples include inviting friends to try the product, creating a social profile, or adding a song to a playlist. Each of these behaviors strengthen the users’ connection to the product. They put in effort, so they value their creation more, and also, they want to be consistent with their past behavior, so they will keep doing it in the future.

From a different perspective, the user’s investment can be storing data, content, followers, reputation (e.g., Airbnb), or skills (e.g., Photoshop).