Ears work as a team, and the brain needs both to process speech and locate sound direction. Hearing with both ears is known as binaural hearing. If you can only hear in one ear (unilateral hearing) it’s difficult to perform the tasks listed below.

Understand Speech in noise
If you can only hear in one ear it makes it more difficult to pick up on quiet speech in a noisy environment. Hearing with both ears also makes it easier for your brain to practice selective listening. This means you can focus on the conversations you want to hear.
Locate sound
Not being able to tell where sound is coming from may cause problems.

For children, it can be hard to understand the teacher in class or the coach on the sports field.
For adults, driving through traffic can be difficult. For both, crossing a busy road could prove dangerous.
Avoid the head shadow effect
When you can only hear with one ear, sounds that come from your ‘bad side’ fall in the shadow of your head.
Sounds have to travel around your head so your ‘good ear’ can send them to the brain. As a result, sounds can be difficult to hear and understand clearly, especially in noise. This is particularly true for higher-frequency sounds.
Enjoy music
People who have lost hearing in one ear say they enjoy music less and describe it as sounding unpleasant, indistinct or unnatural, compared to how it sounded with both ears.

Binaural hearing and speech development in children
Hearing with both ears helps children better understand speech and language. This is important for their learning and development.