It's always important to remember that snakes rarely stay in one place. They do not "nest" in the traditional way. They are typically mobile. Outdoors, venomous snakes should be removed for your safety, but the vast majority of non-venomous snakes outdoors will leave if you let them on their way. Indoors, all snakes should be removed, but once removed, they are unlikely to come back (though other snakes may find a way through the same entrance points). The exception to this is when they have an easily accessible habitat that keeps them safe, and they are not relocated. For example, if you see a snake on your property and scare it away, but you still have rocks or logs that offer a great, warm hiding spot, they may come back. That is why it is important to consider exclusion if you've seen regular snake invasions, or ask a professional to look for burrows that may harbor snakes.