Your eye is like a water balloon. The optical tissue normally allows fluids to flow through the membrane wall, which acts like a filter, supplying nutrition and cleaning out particles, keeping your eye clear so your vision is good.
When the membranes become tough like leather, fluids are trapped, and particles start to build up. If the build up continues, it will seem as if you are looking through frosted glass.
Our eyes should also be flexible, so the muscles can change the eye's contour and focus. When the eye membranes and muscles become tough, the eye cannot focus properly and vision becomes blurry.
When treating irritated eyes, most eye drops and medications deaden the nerves and cover the pain, but the problem is not solved and the discomfort returns. We in turn buy more eye drops to relieve the discomfort.