Re: question
I think it has to do with the ?J? word. If you simply want to use the box as a pull point (no junctions or terminations), then I guess it wouldn?t matter much. But the primary function of a junction box is to provide a location for joining wires. If the junction point ever gets loose, and if the box is covered by the wall, how would you find the box, let alone get into it to make the repair?