users have an accurate mental model of the system? Does the system support the development of an accurate mental model? Step 5, Perceiving what happened: Can the users perceive the system’s state? Does the UI provide the users with sufficient feedback about the effects of their actions? Step 6, Interpreting the outcome according to the users’ expectations: Are the users able to make sense of the feedback? Does the UI provide enough feedback for this interpretation? Step 7, Evaluating what happened against what was intended: Can the users compare what happened with what they were hoping to achieve? Further reading Norman, D. A. (1988). The Design of Everyday Things. New York, Doubleday/Currency Ed. Related terms Gulf of evaluation exists when the user has trouble performing the evaluation stage of the human action cycle (steps 5 to 7). Gulf of execution exists when the user has trouble performing the execution stage of the human action cycle (steps 2 to 4). OODA Loop is an equivalent in military strategy. Human–computer interaction Motor control Psychological models