The answer to 'why is my sink leaking water' is that there are several common causes for a leaking sink, including worn-out washers, loose connections, cracked or damaged sink basins, and issues with the sink drain. The most likely culprit is a worn-out rubber or plastic washer in the sink faucet or drain. Over time, these washers can become dried out, cracked, or dislodged, allowing water to leak out.
Other potential causes include loose fittings where the sink attaches to the countertop or where the drain pipe connects, as well as cracks or damage to the sink basin itself. Leaks can also occur if the sink drain or overflow openings are not properly sealed.