They don't fix hearing, they just make bits louder and add their own electrical noise and random sounds that happen to have some frequencies that are shared with the area of loss into the mix
I wear mine every bloody day and the best bit of the day is taking the fucking thing out so I have the quiet of the HSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSS
instead of the HSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSS
and the SSSSSSSSSSSHHHHHHHHHHHSSSSSSSSSSSSSSSHHHHHHHHHHHHHHHHHHHHHHHHHHHSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSs
and the THUMP THUD tickkkkkkkkkkkkkkkkkkkkkkkkkk BANG of random things happening outside.
and the road noise.
and the other frequencies that are fractionally above and below the loss that don't really need amplifying but are.
and the PAIN of when some fuckers decide to clap their hands or clatter stuff around or sneeze or squeal with laughter. And the random way the AI decides that what you really want is for everything behind you to be amplified even more because there's some bugger making a racket when you just want to hear the mumbler on the phone who is holding it at arms length during a hurricane whilst eating Werther's Originals by the sounds of it.
And with all that, you have people who refuse to face you so you can see their faces move, get botox so you've got nothing to go on, have radios and TVs on all the time, turn away mid sentence, start rustling a bag of crisps, tap tap tap tapping, move around like their legs are made of strawberry boot laces, start talking whilst eating. Oh, and it randomly decides to start complaining at you in computer American - baddery. Baddery. Fucking baddery. And then you need to sort tubes and domes and cleaning filaments and fucking badderies.
Maybe a decent analogy to glasses would be that you get issued with a pair of huge magnifying glasses with flashlight attached - and then people switch off the lights or turn on a football pitch floodlight at the same time as a laser show is going on and somebody's deliberately bouncing light off a mirror into your face at random intervals. When you actually need glasses for a quarter of what you see at a distance of 8 foot and a light tint to reduce glare.