Which of the following statements is true regarding valve lubrication?

The statement that most valves need lubrication is true because many types of valves, especially those that operate mechanically, have moving parts that can experience wear and tear due to friction. Lubrication helps to reduce this friction, ensuring smoother operation and extending the lifespan of the valve. It also aids in preventing corrosion and buildup of debris, which can hinder the functionality of the valve.

Certain valve types might have specific lubrication requirements based on their design and usage, leading to the understanding that while not all valves may need the same level of lubrication, a significant majority do benefit from it to ensure optimal performance. This is especially true for valves that are manually operated or those subjected to frequent use.