Our night caretaker is there for several reasons. Mostly, it’s in case you need something at night. For instance, one time the water pump failed at 8 pm at night (we are on cistern water), and he was able to get it started again. He also can start the generator in case of power failures, or let you in after dinner if you forget the keycode. The infrastructure is not as robust as in the US, and our staff does not have vehicles (many people do not in St Lucia), so by having someone there at night we can make sure you are well taken care of.
It is also partly a security measure. We haven’t had any issues, and the villa locks up securely. But it is located in a fairly secluded area at the top of a hill in a forest, and most of our guests find that having someone there gives them a little extra piece of mind.