Which hinge feature is essential for standard door functionality?

The feature that is essential for standard door functionality is proper gain. Gain refers to the amount of space between the door and the frame, which is crucial for ensuring that the door swings freely and latches correctly. When gain is properly accounted for, it provides the necessary clearance for the door to operate without obstruction, allowing it to open and close smoothly. This is fundamental for the door's overall performance, ensuring that it seals well and maintains security when closed. Proper gain also helps prevent excessive wear on the hinges and the door itself.

In contrast, while weight capacity, adjustability, and durability are important considerations for hinges, they do not directly impact the basic function of the door in the same way that proper gain does. Weight capacity is more related to how heavy a door the hinge can support, adjustability allows for minor corrections to door position after installation, and durability pertains to the lifespan of the hinge materials under various conditions. These are all valuable traits, but without proper gain, even the most durable or adjustable hinges will struggle to perform effectively.