Instead of relying on expensive marketing, habit-forming companies link their services to the users' daily routines and emotions.

As fleeting commitments, diets often fail. Thinking of dietary choices as part of who you are...can give them real staying power

Users who continually find value in a product are more likely to tell their friends about it.

User habits are a competitive advantage. Products that change customer routines are less susceptible to attacks from other companies.

If users are not doing what the designer intended (when users are investing time, effort, etc in your product), the designer may be asking them to do too much.

For an infrequent action to become a habit, the user must perceive a high degree of utility, either from gaining pleasure or avoiding pain.

Like flossing, frequent engagement with a product, especially over a short period of time, increases the likelihood of forming new routines.