OLD Ease of Learning: How fast can a user who has never seen the user interface before learn it sufficiently well to accomplish basic tasks?

NEW Ease of Doing: How fast can a user accomplish the desired task? How much time? How much energy applied per unit of measured time?

Why better? Takes into consideration users doing something versus knowing how to get it done; practical and concrete measures; accounts for situations where learning is not needed nor desired. Deliberately factors out the need for learning, education, or necessary assistance.

OLD Efficiency of Use: Once an experienced user has learned to use the system, how fast can he or she accomplish tasks?

NEW Pain Tolerance: What is the level of pain users are willing to endure to learn a task? How much are they willing to suffer before abandoning the task?

Why better? Takes into account the very real fact that many users are not willing to complete a task if it is too painful or difficult. Especially useful for examining and digging into why tasks and transactions are completed. Why measure speed and efficiency if users never even get the opportunity to become experienced? Further, this breaks the assumption that users must be experienced at all to accomplish a task.

OLD Memorability: If a user has used the system before, can he or she remember enough to use it effectively the next time or does the user have to start over again learning everything?

NEW Recommendability: What is the likelihood that a user will recommend the system to others? If users are willing to recommend, they are willing to use again. Further, if a user recommends the system to another user, it is obviously memorable.

Why better? Word of mouth is the most powerful marketing a system can entertain. It is obviously business oriented and somewhat task focused, but more importantly, it truly focuses on user to user connections which is something lost with memorability, and usability in general. Focuses on networks and social connections of people. Also, while memorability is good for focusing on decreasing costs associated with re-learning it is bad for understanding translation to growth. Recommendability is more positive and focuses on the value of improvements, working with others, and human to human interaction. Bottom line, cost reduction is limited in value whereas growth is not.

OLD Error Frequency and Severity: How often do users make errors while using the system, how serious are these errors, and how do users recover from these errors?

NEW Subjective Severity of Errors: To what extent are users willing to suffer the errors of a system? How intense do users perceive the errors? To what level do errors impact user satisfaction, but more importantly, task completion and recommendability?

Why better? Errors are only errors if users subjectively experience pain. Some users are very forgiving and their task completion may not be impacted at any level. Of critical note, Error tolerance and subjective severity is directly tied to recommendability, which in turn is particularly useful for business and monitoring system profitability.

OLD Subjective Satisfaction: How much does the user like using the system?

NEW Dance to Profit: Is the system good enough to drive down costs and increase profits when considering how users operate as part of the system? What is the financial impact of users on a system? What is the financial impact of systems on users?

Why better? When recommendability is high, error tolerance is high, and subjective severity is low, a poor design system can actually be quite profitable. The Dance to Profit is the measure to ensure that businesses are considering their systems while watching user tasks and the bottom line. For those not as concerned with profitability, simply replace profitability with the most importance measure of success for your system, organization, etc. Look for the measure that keeps the end goal as the end goal, in the context of good user experience.
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