What could lead to depletion of a common resource?

The depletion of a common resource is primarily caused by overuse by individuals. Common resources are typically characterized by their rivalry and non-excludability, which means that individuals can use them freely, but one person's consumption reduces the amount available for others. When individuals exploit these resources excessively, it creates a situation where the resource becomes depleted faster than it can regenerate or be replaced, leading to scarcity.

For instance, if a group of fishermen has access to a common fishing ground and they all overfish, the fish population may decline to the point where it cannot sustain itself, ultimately leading to a collapse of the fishery. This scenario illustrates the tragedy of the commons, where each individual's decision to overuse the resource adversely affects the group as a whole.

While underused resources would likely lead to the preservation of a common resource, non-rivalrous consumption does not apply to common resources since rivalry defines them. Restriction on access might help in managing resources sustainably rather than leading to depletion, as it limits the number of individuals who can consume the resource at a given time.