This can be visualized as a car moving forward,reverse,braking in forward and in reverse.Although it may be or may not be true, but I have used car so that you can understand better than using a motor.
Forward Drive-In quadrant 1,as voltage and current is positive, the rotation is clockwise, and torque is clockwise.So the motor runs forward.
Reverse Drive-here voltage and current is negative, so rotation is anticlockwise and torque is anticlockwise. So the motor runs backwards.
Forward braking-here voltage is positive and current is negative. This means the rotation is happening clockwise but now the torque is applied anticlockwise. So the motor stops eventually.
Reverse braking-here voltage is negative and current is positive. This means the rotation is happening anticlockwise but now the torque is applied clockwise. so the motor stops eventually.