To limit the probability that performance will fall significantly below expectations with respect to materials, underlayment, counter battens, flashing, battens, attic ventilation, tiling procedures, bedding and caulking, which could lead to premature failure, which could lead to water penetrating directly to roof decking or sheathing, which could lead to deterioration, which could lead to the structural failure of roofs or assemblies protected by roofs, which could lead to harm to persons.