We hang a mass (red ball) on the motor to prevent it's rotation. We make the mass heavy enough such that it's Weight Force directly opposes the motor force produced by that wire.
$$mg = BIL$$
Does this motor turn? I feel like the answer is no, because that wire has no net force acting on it (forces cancel out). However, there still is a force being produced by the right hand wire (next to the N pole). It feels like this force should still be able to make the coil turn.