Why should the rear car not have the brakes cut out?

The rationale behind ensuring that the rear car does not have its brakes cut out primarily revolves around safety concerns, specifically regarding the potential for uncoupling incidents. If the rear car's brakes are cut out and the train were to uncouple, that rear car would have no braking capability. This situation could lead to it rolling uncontrolled, creating a significant hazard. Without brakes, there would be no means to stop that car, which could result in accidents or collisions.

Maintaining operable brakes on all cars, including the rear, is crucial for the overall control of the train, especially in emergency situations or when navigating areas with gradients. Properly functioning brakes ensure that each car can be effectively managed, preventing dangerous scenarios that could arise from unbraked cars in the event of a separation.