If you have a fixed mounting method, such as what you’d see on a double shower curtain rod, then the shower rod is screwed into the wall. It won’t fall unless it’s ripped out of the wall. Rubber caps can help to prevent a tension rod from falling. However, even if tension rod has rubber caps, they may not grip the smooth surface of tile. Try gluing rubberized shelf lining material to the end of the rod. This will create more grip and prevent the rod from falling.