A skin treatment device (100) comprises: —a housing (101); —a treatment action performer (110) arranged within the housing (101) for performing a treatment action on the user's skin (2); —a speed sensor (120) for sensing a relative speed between the housing and the user's skin; —a speed feedback signalling device (400); —a control device (140) receiving an output signal from the speed sensor. The control device controls the speed feedback signalling device if the output signal received from the speed sensor is outside a tolerated displacement speed range (R). The tolerated displacement speed range is adapted to the skills of the user to move the device over the skin surface with a constant speed. If the user's skills are relatively low, the control device increases the magnitude of the tolerated displacement speed range.