— Natural language user interfaces for robots with cognitive capabilities should be designed to reduce the occurrence of miscommunication in order to be perceived as providing a smooth and intuitive interaction to its users. This paper describes how miscommunication analysis is integrated in the design process. Observations from 12 user sessions revealed that users misunderstand the robot’s functionality; and that feedback sometimes is ill-timed with respect to the situation. We provide a set of design implications to prevent errors from occurring, to influence or adapt to users’ behavior.