You should have to pump your brakes. Pumping the brakes builds pressure back up in the system that should already have pressure. That means that you either have a leak or air in your system. Both of which are dangerous. Inspect your brake system immediately.
Probably because you've got air in your brake system. You need to bleed the brakes. Open the bleed-valve, pump the brakes till only brake fluid comes through.
You have to pump your brakes because you either have air in your lines or you have a bad master cylinder. Have you had your brakes done lately they may not have bled them correctly. Or I don't know if you have just checked the brake fluid level.
