Nir Eyal says it is a myth that the best product always wins.

For example, when compared in a blind test, Bing get 50% of the users, but in real life, Google has >80% of market share. Most users are already in the habit of using Google, and they just don't stop to consider other options.

Once you can get get a customer to use your product without even thinking about it, then you are no longer competing on either price or features.

Habit-formation is a huge competitive advantage.