Why is it necessary to replace brake fluid periodically?

Brake fluid is hygroscopic, which means it has the ability to absorb moisture from the environment. Over time, as moisture accumulates in the brake fluid, it can lower the fluid's boiling point, leading to the potential for vapor lock in the brake system during heavy braking situations. The presence of water can also cause corrosion inside the brake system, particularly on metal components, which can lead to serious brake performance issues and costly repairs. Therefore, regular replacement of brake fluid is crucial to maintain the integrity and function of the braking system. This preventive maintenance helps ensure that the brakes respond effectively and safely when needed.