I'd go one further than that:
You know the parchment used to line trays before baking?
You'll get a bit of crud on the tray or tin if you don't use that paper.
It's very difficult to get rid of, that crud, and you could be trying for a long time. Years later, and there's traces of it, coz it's burned in. It's made a calamitous mark on the metal, changed it forever for the worse, seared it in a way that is impossible to remove.
That's what those two parties are.