In one of my workplaces, the guy in charge of bathroom maintenance decided for some reason we had to economize on TP, so he had installed brand new 'hangers' where there was a tab on the roller which engaged a small knob or 'stop' thus prohibiting the roller from rolling a full 360, in fact, it couldn't roll more'n 180 degrees. Since the roller was plastic and the knob was metal, those of us with jacknives (all of us) whittled away at yon tabs until we had rollers which would really roll.