To limit the probability of water, from rain or melted snow, running down the face of cladding, entering joints between shingles or shakes, and penetrating the cladding assembly through joints in underlying courses or through corresponding joints between shingles or shakes in lower courses, which could lead to precipitation or meltwater ingress, which could lead to deterioration, which could lead to the structural failure of exterior walls or elements protected by exterior walls, which could lead to harm to persons.