Hydraulic brakes can fail for one of two reasons. Which of the following is one of those reasons?

Most hydraulic brake failures occur for one of two reasons. A first likely cause of brake failure is that the brakes have been overused on a downgrade, causing them to fade. The second likely cause is that there has been a loss of hydraulic pressure in the braking system. Brakes kept in good condition will rarely fail, but you should know which steps to take in case they do.
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