What is the main function of an engine cut-off switch?

The main function of an engine cut-off switch is to shut off the engine if the operator is thrown overboard. This safety feature is critical for preventing the boat from continuing to operate without its operator, which could lead to dangerous situations, such as the vessel running in circles or colliding with obstacles or other boats. In the event that the operator is unexpectedly ejected from the boat due to a sudden movement or accident, the engine cut-off switch ensures that the engine is immediately deactivated, significantly reducing the risk of injury and creating a safer environment on the water.

Other options like starting the engine remotely or increasing the boat's speed do not relate to the primary safety function of cutting off the engine. Similarly, while preventing fuel leakage is also important for safety, it is not the role of the engine cut-off switch.