Advantages of wearing two hearing instruments include:

Improved localization of sound
The ability to detect the direction and distance of sound can only be achieved with two ears.

Balanced hearing
Hearing with two ears will help you more accurately respond to sounds, such as conversation occurring on either side of you.

Better speech comprehension
Balanced hearing with both ears may improve your ability to understand speech, both in background noise and in quiet situations.

Comfortable and less tiring listening
Conversations will be more pleasant and you will feel less fatigued from concentrating on what is said.

Keep both ears active
Wearing one hearing aid when two are required might result in greater deterioration of the hearing in the unaided ear.