Improving user-interface dependability through mitigation of human error

Two security-sensitive user interfaces were evaluated in a laboratory user study: the Windows XP file-permissions interface and an alternative interface, called Salmon, designed in accordance with an error-avoiding principle to counteract the misleading constructs in the XP interface. The alternative interface was found to be more dependable; it increased successful task completion by up to 300%, reduced commission of a class of errors by up to 94%, and provided a nearly 3× speed-up in task completion time. Moreover, users spent less time searching for information with the alternative interface, and a greater proportion of time on essential task steps. An explanatory theory in its early stages of development is presented.