Welcome to our forum.
...Maybe it's just the thought and hassle of getting undressed...
If a tub is outdoors in a cold climate, proximity to the house is critical. If I had to walk very far, I would probabaly rarely use it....My tub is about 4 feet from my back door..I love it outside because it gives us a chance to experience the winter in a way so different than we ever have. My husband HATES winter, snow..cold anything to do with it..But because we have the tub, he claims he can now enjoy it..So for us, it needs to be outside..but close to the house