What is the purpose of tying a stopper knot in the end of the rope before descending?

Tying a stopper knot at the end of the rope before descending serves a crucial safety function by preventing rappelling off the end of the line. When you're descending, especially in rescue operations or climbing scenarios, it's vital to ensure your safety and the effectiveness of your equipment. By utilizing a stopper knot, you create a physical barrier that ensures the descending climber or rescuer cannot inadvertently slide past the end of the rope. This is particularly important in situations where the end of the rope may not be visible or when the rope is under tension, as it minimizes the risk of falling and potentially sustaining injury.

While there might be other reasons for using knots in various contexts, such as marking the end of the rope or facilitating climbing, the primary concern in the context of descending is safety. The presence of a stopper knot can help you focus on the task at hand without the added worry of misusing the equipment or experiencing an unsafe descent.