I am so frustrated, I shut our main water supply off and this tub is still leaking! Why? I haven't replaced the washers yet, havent had time, but I thought if I shut off the main it would buy me some time. Am I crazy?
If your trying to shut it off with an old style globe or gate style shut off it's very common for it not shut off completly or at all in some cases.
Trash gets stuck in the sealing surface, the stems leak or can completly snap off inside the vales.
Replace it with a ball valve and it will shut off every time.