Nir Eyal quotes:

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

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

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

Companies leverage two basic pulleys of human behavior to increase the likelihood of an action occuring: the ease of performing an action and the psychological motivation to do it.

Fogg states that all humans are motivated to seek pleasure and avoid pain; to seek hope and avoid fear; and finally, to seek social acceptance and avoid rejection

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

The aim is to influence customers to use your product on their own, again and again without relying on overt calls to action such as ads or promotions.

Brainstorm new interfaces that could introduce opportunities or threats to your business.

Habit-forming products alleviate users' pain by relieving a pronounced itch.

Products with higher user engagement have the potential to grow faster than their rivals.

Reducing the thinking required to take the next action increases the likelihood of the desired behavior occurring unconsciously.

When designers intentionally trick users into inviting friends or blasting a message to their social networks, they may see some initial growth, but it comes at the expense of users' goodwill and trust. When people discover they've been duped, they vent their frustration and stop using the product.

Why not live now instead of someday?

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

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.

Many innovations fail because consumers irrationally overvalue the old while companies irrationally overvalue the new.

The ultimate goal of a habit-forming product is to solve the user's pain by creating an association so that the user identifies the company's product or service as the source of relief.

To initiate (user) action, doing must be easier than thinking.

You'll often find that people's declared preferences - what they say they want - are far different from their revealed preferences - what they actually do.

Habit-forming products often start as nice-to-haves, but once the habit is formed, they become must-haves.