Politeness cannot make up for robots’ errors

We investigated the impact of robot politeness and error-prone behavior on user perceptions through two user studies involving non-humanoid robots. Politeness was operationalized at two levels based on Lakoff’s, (1973) politeness rules—one condition implemented all three of Lakoff’s rules, demonstrating the highest level of politeness, while the other omitted them, resulting in a behavior that was strict but not impolite. The correctness was manipulated by comparing an error-free robot behavior to a behavior that included intentional errors. The studies were conducted using two different tasks with two robot types—a mobile robot and a manipulator robot—and involved 59 young adult participants (ages 24–28) with engineering backgrounds. Participants consistently rated the correct and polite robots most favorably. However, politeness did not offset the negative effects of erroneous behavior. In both studies, the robot that was correct but strict was rated more positively than the one that was polite yet made mistakes. These findings suggest that, at least in utilitarian task settings involving technically proficient users, politeness alone cannot compensate for performance failures. Moreover, a polite robot that makes errors may even frustrate users more than a straightforward but accurate one. The findings also emphasize the importance of evaluating HRI performance across different robot types and tasks, as these factors significantly shape user perceptions.