Being partly deaf can sometimes be advantageous
I've been mostly deaf in my left ear since birth. The last test I had, about five years ago, put my left ear at about 20% of "normal" and my right ear about 80%. I use normal in quotes because that percentage covers the entire range of frequencies; in reality I hear a higher percentage of sound in the upper and lower frequencies, but much less than 20% in the more-important middle frequencies.
Voices, music, those kinds of things.
I am fortunate enough that it only affected one ear, and that I was born with it — and thus didn't need to adapt to it at a later stage in life.
My feeling is that it has gotten worse with age, due to the fact I find myself saying "pardon?" or "蛤?!" ("what?!") more and more often.
Still, I continue to do what I've always done in social situations; try to position myself on the person's or people's left, and do so as naturally as possible. On a table of four or more, I'll always sit at one of the left corners. (This also helps with chopsticks, as I use them left-handed, and thus no collisions occur.)
Most people I have met don't realise, and that's the way I prefer it. I don't want a fuss. Over the years I have accepted telling people more often, just so they're aware. (Likely also my feeling guilty for their having to repeat themselves more often.) When the topic comes up, people sometimes ask me whether I have considered a hearing aid.
I answer the same way; that because I was born with it, I'm used to how sounds are balanced. The same as when I wear headphones. I'm used to music being balanced the way it is. When I try to use software to boost the left side, it sounds wrong, somehow. Some songs, like David Bowie's Sound and Vision, are just better through speakers.
Anyway, onto the advantage I spoke of in the title. The advantage is while sleeping. If there are noises that disturb my sleep – road noise, dogs barking, snoring – I can just turn to lie on my right side, left ear upwards, and... blissful silence.
Believe me, it comes in useful quite often.