Physical deterioration results from:

Obsolescence refers to the process by which a product becomes outdated or no longer useful due to newer alternatives or changes in technology. While it may lead to items being discarded, it does not directly cause physical deterioration; instead, it reflects a shift in relevance rather than physical condition.

Reversion typically refers to the process of returning to a previous state or condition, often used in legal or biological contexts. It does not pertain to physical deterioration, as it does not involve the gradual degradation of materials or objects but rather a return to an earlier form or state.

Accretion involves the gradual accumulation of additional material or mass, often seen in geological processes or the growth of objects through layering. While it can alter the physical properties of an item, it does not lead to deterioration; rather, it can enhance or change the physical state of the object.