Likewise reflections of strong light from eyeglasses are often very annoying, and in the street may be very dangerous. Expensive coatings are needed to reduce these effects. In so doing, they reduce the brightness of colors. These coatings also require special cloths to clean, and they scratch easily requiring a hardness coating. Many people have great difficulties with glasses because of the activity of their lives, which not only leads to the breaking of the lenses but often throws them out of focus, particularly in the case of eyeglasses worn for astigmatism.
Contact lenses are difficult to clean and maintain.
They are often dropped and lead to various eye diseases if not scrupulously cleaned. Astigmatism is often corrected poorly, due to the lens rotating on the eye. Even the most permeable contacts deprive the eye of oxygen and frequently capilaries begin extending into the cornea as a result. Extended wear lenses are notorious for causing infections and complications. The progression of myopia often means that a perfect prescription is quickly inadequate and the the patient spends most of his or her time with a noticeable amount of refractive error.