According to Thomas Baekdal, usable sites/apps are fast, efficient, simple, (and focussed).
- Fast is connected to “GOMS keystroke model”
“The fewer times you click on something and the fewer times you move your hand between the keyboard and the mouse, the faster it is to use”.
- Efficient is connected to “Fitt’s Law”
“A large target close to you, is easier to hit than a small target far away”
- Simple is connected to “Hick’s Law”
“The fewer choices you have, the easier it is to choose between them”