A relative of mine is on the point of giving up the car - he's in his seventies, hearing aids both ears, (arguably can't hear emergency service sirens), can't drive at night due to eyesight problems -fine in the daylight.Yet during his working life, he had a fast motorbike as a 20 something, and spent most of his later life working for a utility company driving all over Derbyshire - he probably knows more shortcuts to various locations in our county than FLY.
Yet we've noticed he labours the engine by putting it in to a higher gear than he needs to, because he can't hear the engine note - e.g. he'll stick it in 4th gear uphill when 3rd would be best.
He has however got the equivalent of Hyacinth Bouquet for a passenger!!
He has had a couple of minor incidents shall we say recently, but they like to get out and about whilst they still can, & I don't blame them.
My Dads in his 80's (ex - bus driver too), and he's still towing a caravan around with his Nissan Quashqai, probably holding the rest of the world up (bus drivers speciality)

They'll give up eventually - and then get on the bus at 09.30 exactly with a free pass and moan because I'm 2 minutes late, or the bus it too hot/cold, or can you drop me off at my door (no - for insurance reasons), and keep wandering up to your bus stop when you should have left 3 minutes ago, get on your bus, and then start firkling (I like that word) around in each & every pocket for their pass.
STOP IT - I'M RANTING AGAIN. Must calm down
You take my points about the majority of my "sane" post though 