The adhesive doesn't stick the rubber, as other reviewers have commented. The adhesive seems to be this odd goo that's not all that sticky, and the rubber disk that's supposed to hold your cord slowly slides off and falls to the floor.
This was really a waste of money. I thought maybe I just got a bad batch. The adhesive was so unsticky I thought it had expired in a warehouse somewhere, but apparently other people are having the same issue.