Les Jones

E-commerce > Joel Sposky's "Usability in One Easy Step"

His latest:

Something is usable if it behaves exactly as expected.

That's it! That's the whole story! As Hillel said, all the rest is commentary.

That's pretty similar to Jakob's Law of the Internet User Experience:

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.