Eardrum perforations are caused by infection or injury in your ear, and can affect your hearing or make you more prone to recurring ear infections. 

An eardrum perforation affects your hearing because the hole stops the eardrum from vibrating optimally, which affects the impulses passed via the auditory nerve from your inner ear to your brain.

The perforation can also allow germs to enter into deeper parts of your ear where they would not normally be able to reach, causing a potentially serious infection. This probability of infection is increased if you immerse yourself in water such as while swimming or bathing. 

If a torn eardrum doesn’t heal on its own, a myringoplasty is a surgical procedure that can be done to repair the perforation in order to prevent further infection and restore your hearing.