Fading refers to a reduction in braking power when the brakes are used heavily, such as continuous braking during downhill driving through mountains. The cause of fading is poor dissipation of the frictional heat generated during braking and, in extreme cases, can lead to red hot brake discs. Fading can lead to distortion of the brake discs or drums, or to the formation of vapour bubbles in the brake fluid.
Your SEAT model effectively counteracts brake fading by using sufficiently large brakes and disc brakes on the front and rear axles. Ventilated disc brakes on the front axle further reduce the risk of fading.