My laptop has a plastic chassis whose panels snap (no screws to the outside). When I bought it (new), there was a gap of one side along the seam joining the upper and lower halves of the chassis (gap of one inch by 3-4 mm) . That is, one of the "brackets" was not clicked in place. In addition, the panels are not quite aligned with the USB port whose lower edge merges with the seam on the same side (it might have been used to force it to open?).
Is this an indication that it may have been changed somewhere along the line? The box was sealed and looked good.