There are many people who have a total deafness in one ear but excellent hearing in the other ear, and these people are frequently thus affected from early childhood— even from birth. They do not have to adapt themselves to the lack of hearing in one ear because they have never known binaural hearing and hearing with one ear seems natural to them. Unless they lie on their good ears so as to prevent the entrance of sound they may not know they are monaurally deaf until they are well into their 20's.
There are many people who have no usable hearing or are totally deaf in one ear and also have a considerable or even a severe loss of hearing in the other ear. These people derive great benefit from properly fitted hearing aids, but they do not hear or utilize sounds coming from the opposite side of the
FOWLER EP. Bilateral Hearing Aids for Monaural Total DeafnessA Suggestion for Better Hearing. AMA Arch Otolaryngol. 1960;72(1):41–42. doi:10.1001/archotol.1960.00740010045007