What essential feature should weatherproof cables have according to installation guidelines?

Weatherproof cables must have a waterproof coating as an essential feature according to installation guidelines. This is crucial because these cables are often installed in outdoor or damp environments where exposure to moisture is a significant concern. The waterproof coating prevents water from seeping into the cable, which could lead to short circuits, corrosion, and ultimately, cable failure.

While UV resistance, flexibility in extreme temperatures, and the ability to self-repair are valuable attributes for different types of cables, they do not specifically address the immediate need to protect against water ingress. The waterproof coating directly ensures the cable's longevity and functionality in adverse weather conditions, making it a foundational characteristic for weatherproof cables.