Gimme FIve

Will five users really find 85% of all usability problems? Diese Frage beantwortet Measuring Usability in gewohnt übersichtlicher Manier.

Most people can understand that there is a diminishing return with testing users. Fewer believe you can actually quantify the percent of problems found and so are dubious when they hear claims such as five users can detect 85% of problems. There's good reason for the skepticism--they're right, you can never know the total number of problems (if you did you'd go and fix them). Instead, you can only quantify the percent of problems found given problems that affect a certain percent of your users given a specific set of tasks.

Ein guter und interessanter Beitrag.