How can you get suction cups that stick to the shower tile?

This is how to make suction cups stick in the shower.

Before applying the suction cups, make sure that both your window and the inside of the cups are dry and clean. A small amount of Vaseline, cooking oil, or a little water can be used to moisten the suction cup's inner rim.

How can you improve suction cup adhesion in the same way? To clean the suction cup, rinse it in warm soapy water and dry with a soft cloth. Make sure to clean the surface where you're applying the suction cups. The suction cup won't stick to a dirt surface. A tiny amount of Vaseline, or cooking oil can be used to improve suction.

This is why suction cups cease to work.

The seal of the suction cups is imperfect so air can slowly leak inside. If there is no air pressure differential between the cup and the wall, it won't slide down the wall because there is no friction.

How can you fix a suctioncup that doesn't stick to the surface?

The suction cup will stick to any surface if there is a small amount of oil or petroleum jelly around its lip. The chosen substance should be applied to the cup's perimeter so that it sticks onto another surface. You should use as little as possible to maintain suction power.