Some goods, such as lighthouses, can switch between being public goods and being private goods depending on the circumstances.

Lighthouses can be considered public goods because they are non-excludable and non-rivalrous, meaning anyone can benefit from them without reducing their availability to others. However, through mechanisms like charging ships for navigation services, they can be operated as private goods, where access is restricted to paying customers, thus depending on the circumstances, they can switch between being public and private goods.