Ghosting in the Construction of a House?

There's a term called ghosting. In the world of building and painting, house painting, ghosting usually refers to these dark streaks or patches on walls or ceilings or even carpets. And for most people, they're unexplainable. Where did this come from? You know what i mean? Especially in an older building, people may have very valid concerns about contaminates as they're lead. Paint, as they're is better, and so on. But this, i posit doesn't sound like exactly the same thing, because it sounds as though these hand prints just appeared, right? Ye?