When it comes to taps there are 3 main types. Jumper valve. Ceramic disc. Cartridge. They all control the delivery of water just in different ways. Jumper valves: Jumper valves rely on a washer to control the flow of water by lifting up of a brass seat when the handle is turned on (righty tighty, lefty loosy). Over time the washer gets worn out or a groove called pitting occurs in the brass seat. Its similar to how water has created the grand canyon, just on a way smaller sc