It is hard for most of us to imagine a totally silent world, and there are actually very few people classified as deaf who can hear absolutely nothing. Most deaf people hear a blur of noise that is not quite comprehensible, and this can be more annoying than total silence. The worst affected are those who cannot hear any intelligible sound, and are sufferers from tinnitus (a constant buzzing in the ears).
If excessive quantities of wax, or a foreign body (e.g. tiny toy or foam packing ball in children) blocks the outer ear canal, hearing will be reduced in that ear.
The gradual decrease in hearing associated with advancing age (presbycusis) is the most common form of deafness. This is basically due to thickening of the eardrum, wear and tear on the tiny bones that conduct the vibrations of the eardrum to the hearing apparatus in the inner ear, and a loss of sensitivity in the spiral tube (cochlear) that senses the vibrations, and turns them into nerve impulses in the brain. The higher frequencies of sound disappear first, and this cuts out a lot of hearing discrimination, so that conversation in a noisy room melts into a constant blur of sound.