Leaking faucets are caused by old washers. Over time, they wear out, crack or break. A leaky faucet can be a source of irritation, especially late at night when there are few sounds to mask the steady dripping of water into a sink. When water leaks from the spout, the source is almost always a worn seal in the valve mechanism or a defect in the mechanism itself. The only other way for water to reach the spout would be through a pinhole leak in the faucet body.