A hair care appliance including a motor for generating an airflow through the appliance, the motor comprising: a frame for supporting a rotor assembly, the frame including an outer wall; and a rotor assembly including a shaft and an impeller, the impeller including a plurality of blades. An impeller housing portion of the outer wall surrounds the impeller. An inner surface of the impeller housing portion includes at least one groove extending in an axial direction and positioned such that the at least one groove extends along at least the axial extent of the blades of the impeller.