What should always be ensured for wiring used in outdoor lighting?

For wiring used in outdoor lighting, it is crucial to ensure that it is weatherproof. This characteristic is essential because outdoor environments expose wiring to various weather conditions, including rain, humidity, snow, and extreme temperatures. Weatherproof wiring is designed to withstand these environmental factors, which prevents the degradation of the insulation and reduces the risk of electrical failures, short circuits, or potential hazards such as fires or electric shocks.

Wiring that is weatherproof typically uses materials and coatings that protect against moisture, UV light, and temperature variations. This level of protection is vital for maintaining the integrity and safety of the electrical installation throughout its service life. On the other hand, while cost-effectiveness, high gauge, and flexibility are important factors in choosing wiring for various applications, they do not address the primary concerns that arise from outdoor exposure to the elements. Ensuring electrical safety in outdoor lighting fundamentally hinges on the wiring's ability to resist weather-related degradation.