The lights, wiring, and other electrical gear mounted on a sailboat's mast most certainly live a hard life. They're exposed year-round to wind, salt, rain, and sun, so it's no wonder that they're so prone to malfunction. What's more, reaching them and fixing them is often no easy task. Because most of these masthead devices are also critical to safety and navigation, installing them properly and maintaining them faithfully is a must.
If a masthead tricolor goes dark, a converging vessel may not see you until too late. If a strobe doesn't work when you need it most-you're in distress or about to be run down-you may not get the chance to discover why it failed. Likewise, if the masthead-mounted VHF antenna stops sending radio signals because the coaxial cable is saturated with water or the connector wasn't properly soldered, you may find yourself cut off just when you need reliable communication.