System Feedback (10)

Upon risky actions (e.g. remove something) the website uses confirmation prompts
There are timely notifications for upcoming delays (e.g. when authorizing a credit card transaction)
There are progress indicators for expected delays in the loading of pages, and the most significant content is shown first
Instructional dialogues give exact steps for action - not advice
The interface provides clear feedback when a task has been completed successfully
Fitts' Law is followed (the distance between controls and the size of the controls is appropriate, with size proportional to distance)
The entered data is kept after work has been discontinued due to any reason
Error alerts are straightforward and provide details for the problem
The user is shown if their work has been saved or not (e.g. via a visual indicator in the title)
There are suitable selection controls to replace the need for typing