Why is a street address not a valid legal description for a deed?

A street address is not a valid legal description because it does not define the exact boundaries of a parcel with sufficient precision for legal purposes. Addresses can change when streets are renamed or municipalities reorganize numbering systems, and they do not specify how much land is included in the parcel. A legal description must identify one unique parcel with enough specificity that a surveyor could locate its exact boundaries on the ground.