Why is nailing a metal cap on top of a pole not considered roofing?

Nailing a metal cap on top of a pole is not considered roofing because it does not provide sufficient protection against moisture and does not serve the primary function of roofing, which is to prevent water intrusion and protect the underlying materials. Roofing systems are designed to create a barrier against the elements, especially water, and ensure that structures remain dry and structurally sound. While a metal cap may provide some level of protection, it lacks the comprehensive water-shedding capability and installation methods associated with traditional roofing materials. Additionally, the function of roofing includes managing drainage and directing water away from the structure, which a simple cap would not accomplish. This distinction highlights why the act of capping a pole falls outside the definition and purpose of roofing.