Michigan lakes area. It is sometimes really windy and really cold for long periods of time. The kind of climate where we get ice in the inside of our windows. Any mechanics needed to have a mechanical doorbell would also let in cold air.
Edit: apparently there are some that have mechanics that pass through the wall that are similar to a door handle and can be sealed up pretty well. Very cool!
the doorbell is inside my house, the spring and pulleys too, he only bit exposed to the outside is a lever you pull to make the contraption move, it is kinda like the launcher on a pinball machine