In a civil proceeding what happens if a defendant changes addresses but does not provide a new one? He stops replying and a default judgement is imminent. Assume that a least one piece of registered mail was confirmed to have been received by him. Would all of this be a nonissue up to the point where the judgment is to be enforced? Would a private investigator be hired to find his whereabouts and then a bailiff would be used to enforce the order? What if instead of property, a monetary order was made. How would it be possible to enforce wage garnishing?
What exactly is the intent behind using registered mail? In apartment buildings the concierge signs for mail and in other scenarios the intended recipient may not be the one who happens to answer the door when the courier knocks.