Ask yourself:
Is it a tight fitting ring? Or does it fit rather loose?
If it fits real tight, the loss must have been in a situation where there is some sort of either or and lubrication or forced use of said hand was involvbed, possibly your car needed some mechanical attention? Or you were doing the dishes, and scrubbed something really hard and it slipped off?
Of course, it could be involving some other lubricant, and now be in some person's ass. Done any fisting lately? There you go!
You are welcome!