A carbon brush is a small yet essential component in vacuum cleaner motors, responsible for conducting electricity between the stationary and rotating parts of the motor. Made from carbon or graphite, these brushes maintain contact with the motor's commutator to ensure the continuous flow of electrical current as the motor spins. Over time, the brushes wear down due to friction, which can lead to poor motor performance, sparking (arcing), or even motor failure if not addressed. Replacing worn carbon brushes is necessary to maintain optimal motor performance, prevent overheating, and extend the motor's lifespan. Regular maintenance of these brushes ensures the motor continues to function efficiently and avoids damage to key components.