A closing aid for a motor-vehicle lock enables fast opening for a lock having a rotary latch. The rotary latch is latched by at least one pawl in a preliminary latching position and in a main latching position. The closing aid comprises a motor, by which the rotary latch is moved by motor force from the preliminary latching position into the main latching position such that an associated door or flap of a motor vehicle can be closed. The closing aid has a movable closing pawl for closing by motor force. By the motion of the closing pawl by the motor from an initial position into an end position along a first path, the rotary latch is brought from the preliminary latching position into the main latching position. The return motion of the closing pawl from the end position into the initial position occurs along a different, second path.