I wonder if some peoples came off because they weren't put on all the way. One of mine snapped right on, the other I thought I had on, but never felt the click on. I had to pull pretty hard for it to come off but it did. In order for me to get that one to click, I literally had to lean on it will all 220 of my pounds against a bench, then I finally felt the click. I tried briefly to get that one off a few days ago and it won't budge now. I hope I can get it off to put my new ones on.