Users spend most of their time on other sites. This means that users prefer your site to work the same way as all the other sites they already know.

The more users' expectations prove right, the more they will feel in control of the system and the more they will like it.

What we learned is money doesn't grow on trees.

To design an easy-to-use interface, pay attention to what users do, not what they say. Self-reported claims are unreliable, as are user speculations about future behavior.

Designers are not users.

Compared to 1999...we cannot quite declare victory, but we can declare progress.

Consistency is one of the most powerful usability principles: when things always behave the same, users don't have to worry about what will happen. Instead, they know what will happen based on earlier experience.