Maintenance of a transportation device propelled by an electric motor, wherein an incremental encoder senses motion of a moving part of, or a part moved by, the electric motor, may include acquiring a pulses-per-rotation configuration value PPRconf, representing a quantity of pulses which should be provided by the incremental encoder per one rotation of the electric motor; deriving a pulses-per-rotation estimation value PPRest representing a quantity of pulses provided by the incremental encoder per one rotation of the electric motor; determining a pulses-per-rotation error value PPRerr representing a deviation of the pulses-per-rotation estimation value PPRest from the pulses-per-rotation configuration value PPRconf, based on a relation: PPRerr=PPRest−PPRconf, PPRconf−PPRest, PPRest/PPRconf, or PPRconf/PPRest; and utilizing the pulses-per-rotation error value PPRerr to generate an instance of maintenance information indicating that a maintenance operation should be performed on the transportation device.