How often should one consider changing a serpentine belt, a seemingly inconspicuous yet critical component of vehicle operability? The serpentine belt, responsible for driving multiple peripheral devices in an engine, plays a pivotal role in maintaining the harmonious function of components like the alternator, power steering pump, and air conditioning compressor. Given its significance, are there specific indicators or recommended timeframes that one should adhere to in order to prevent potential mechanical failures? Furthermore, should motorists take into account varying driving conditions, such as extreme temperatures or heavy loads, which might accelerate wear and tear? Could the age of the belt itself be a determining factor in its replacement schedule, or is mileage the more telling metric? Additionally, how might one recognize the subtle yet telltale signs of impending serpentine belt failure? Considering all these facets, what best practices should be followed to ensure optimal performance and longevity of this essential automotive component?