Earlier quoted context omitted.
The perfect UX is the interface is that displays and works exactly how the user wants and expects. The perfect UI is the interface that has the quickest, most optimal workflow to accomplish a user's tasks
> quickest, And this can be scientifically measured by mouse distance and clicks. > most optimal workflow to accomplish a user's tasks And this can be scientifically assessed by taking all use cases and refactoring over them. List all the available goals at any given "location" in the program. List all the steps users take to get accomplish their goals. Consolidate and refactor, then optimize on the shortness, obviou…
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> And this can be scientifically assessed by taking all use cases and refactoring over them.
And I can't count the number of times I've seen applications do this, resulting in a terrible UI that is hard (and therefore slow) to use.