Pinwheels can get soggy overnight, especially if they are exposed to high humidity or stored improperly. If pinwheels are stored in an airtight container away from moisture, it can help keep them from becoming soggy. Pinwheels that have been exposed to moisture for too long will begin to lose their texture and flavor due to the breakdown of the dough. To avoid this, make sure to store your pinwheels in a cool, dry place and consume them as soon as possible after preparing them. Additionally, you can add an extra layer of protection by adding a thin layer of oil or butter on top of the pinwheel before storing it. This will assist in locking in the moisture and keep it from becoming soggy.