A floor cleaning machine can comprise a chassis, a cleaning mechanism, a control system, and a cleaning operation sensing system connected to the chassis. The chassis can be configured for movement along a cleaning path. The cleaning mechanism can perform a cleaning operation. The liquid system can provide liquid to the cleaning mechanism. The recovery system can recover liquid from the cleaning operation. The control system can control performance of the cleaning operation. The cleaning operation sensing system can detect a condition of the cleaning operation. The cleaning operation sensing system can comprise a water trailing detection system comprising: a frame connected to the chassis aft of the recovery system; an absorbent medium connected to the frame; and a moisture sensor in communication with the control system to alter a signal in response to moisture in the absorbent medium.