One with a poor finish, yes. It is always out in the weather, and on the coast that means salt and damp all year round. Over time it becomes pitted, the rotating cover plate seizes and, on magnetic ones, the cover stops sliding.
That is why in Torrevieja and the surrounding area we suggest escutcheons with finishes designed for outdoor use. They hold up much better, especially on the seafront or on doors that open onto the terrace.
And a tip we always give: wipe the escutcheon with a damp cloth and then a dry one from time to time, especially in summer. It removes the salt before it does any harm.
If your escutcheon has already seized or is pitted, it can be cleaned and adjusted or replaced with another. It is all in escutcheon installation.