Heuristic evaluation is a usability inspection method where 3-5 evaluators examine a user interface and judge its compliance with recognized usability principles called "heuristics." Each evaluator independently explores the interface twice and notes any violations of heuristics, such as consistency, visibility of system status, or flexibility of use. Evaluators then aggregate their findings and rate the severity of identified usability problems to prioritize fixes. With 3-5 evaluators, heuristic evaluation typically identifies around 75% of usability issues in a cost-effective manner.