Originally Posted by
RH Clark
My take is that if you are the kind of rider who barrels down mountains like you are immortal, then you better know the manufacture's recommendations for service, and either be a darn good mechanic yourself or have one on standby. The way I ride, I could likely stop with my foot even if they failed, which they likely won't, just all at once.
Even the most daredevil rider racing down alpine switchbacks, needn't worry.
Contaminated brake fluid doesn't cause sudden brake failure. As the fluid absorbs water it becomes compressible. This eventually manifests as spongy feel, and gets worse very slowly giving you plenty of time to deal with it.