One thing that can be really annoying is cloudy shower doors. You scrub and scrub but they don’t come clean. Usually the problem is hard water stains. You might also notice this problem on windows where you water your outside plants. If the stains are not too bad, 0000 steel wool might take them off. CLR can also be effective. Be sure to try to test first in a spot that won’t be noticed to make sure you are not damaging the surface.