There is this situation called “The tragedy of the commons”. The TL;DR is that the commons within a system are less taken care of than the individual possessions.

For a system to behave at its maximum capacity, you must enforce a framework around the commons. It usually takes various forms, with legal/regulatory ones being the most widely spread approaches.

However, we often seem to forget how much we can collectively achieve if there would be reliance on not-so-easily enforceable but mutually agreed views on the matter.

That being said, though not ethically required, the most effective policy is maximal transparency of intentions concerning the common goods.