Physical deterioration results from:

Obsolescence refers to a state where an item is no longer useful or relevant due to advancements in technology or changes in consumer preferences. While it can lead to items being discarded or replaced, it does not directly cause physical deterioration. Instead, obsolescence is more about a product's relevance rather than its physical state.

Reversion involves returning to a previous state or condition, which does not inherently relate to physical deterioration. It suggests a change or regression that may not necessarily include any physical degradation. Thus, reversion is more about a shift in status rather than an indication of deterioration.

Accretion refers to the gradual accumulation of matter or growth, which can sometimes enhance a structure or object rather than deteriorate it. It is generally associated with building up rather than breaking down. Hence, while accretion can affect physical aspects, it does not contribute to deterioration.