How does reduced brake performance commonly manifest?

Reduced brake performance is characterized primarily by the need for more force on the brake pedal to achieve the same level of deceleration or stopping power that the driver is accustomed to. This increase in pedal effort indicates that the braking system may be deteriorating or that there is an issue such as air in the brake lines, wear on the brake pads, or a malfunctioning brake booster. When the brakes are not functioning as intended, the driver has to apply more pressure to the pedal to exert the necessary force to slow down or stop the vehicle, which can create a safety hazard.

In contrast, while increased vehicle speed might occur due to reduced brake performance, it is more a consequence of the failure to stop rather than a direct manifestation of the reduced brake capability itself. The shaking of the car could indicate a different issue, such as warped brake rotors, but is not a universal or typical sign of overall brake performance reduction. Lastly, activating the cruise control during a loss of braking efficiency would be counterintuitive and dangerous, as it would further complicate the ability to reduce speed or stop effectively. Therefore, the correct manifestation of reduced brake performance emphasizes the additional effort needed on the brake pedal.