For many people, poor weather on days that they have to themselves can be incredibly restrictive. Obviously, you only have so much time to engage with your hobbies and relax, so this can be disheartening. However, getting into the habit of preparing some backup activities can help you see a whole other side of what rainy days have to offer.
They can make it more difficult to go outside and enjoy activities that take place there, true, but they can also provide the ideal conditions for ways to relax and get comfortable within your home.