Being the first point of contact for water in the shower, the shower head is often the place where buildup first noticed . Glass however is, a substance that my take months or even years to show the true destructive nature of mineral buildup.
Though glass is normally thought of as a hard substance, it is surface is really very holey and is therefore quite soft and susceptible to the insight of minerals. As lime scale builds up on the glass over time, it begins to engrave or eat away at the surface. The high humidity levels of the shower accelerate the destruction of the glass. Further, bacteria to grow in the damp, humid pores of the glass surface.
If left untreated, the glass will begin to appear cloudy from the mineral buildup and the concentration of bacteria on the surface will become unhygienic. Once this point is reached, it is very hard to fully remove the scale and bacteria’s. The safest and most effective solution is to replace the glass.
As mentioned above, the buildup scale on glass can take years and most people will convince themselves during the first years after a new shower enclosure purchase that they did not in fact need any surface protectant