Investments in a product create preferences because of our tendency to overvalue our work, be consistent with past behaviors, and avoid cognitive dissonance. Investment comes after the variable reward phase, when users are primed to reciprocate. Investments increase the likelihood of users returning by improving the service the more it is used. They enable the accrual of stored value in the form of content, data, followers, reputation, or skill. Investments increase the likelihood of users passing through the Hook again by loading the next trigger to start the cycle all over again.
