My late DF was one such. He was a truly appalling driver. He passed his test on his 6th attempt, I can only think that the examiner passed him just in case he ever had to test him again. He once managed to crash into a petrol pump when leaving a petrol station. He claimed he "forgot" that his wheels weren't straight when pulling away, ffs.
He never should have been given a licence imo. He gave up driving at 70, and I don't know how he kept his licence so long. He'd had several traffic offences, including at least 2 for driving without due care and attention, and more accidents than I could count.
The reason I feel so strongly about this is that I worked with a woman who passed her test on the 14th attempt. She was an appalling driver yet people were all "yay! Well done you!"
She damaged four cars in the staff car park in the first year of having her license, had three near misses with pedestrians that she was adamant just "appeared" in the middle of the road and then wrote off her car because she didn't like to stop at roundabouts in case she stalled.
I think driving test standards should be higher - there should be limits on what you can do in the first couple of years of driving (it's madness that shortly after passing my test I could have legally taken my 9 month old twins onto the motorway without a second of motorway experience) - and there should be periodical re-testing of people.
Medical and eye exams should also be regular and mandatory.
I also think there should be harsher penalties - if you lose your license a second time (for example) you shouldn't get it back.
Driving is a privilege, not a right. And I say that as someone with a disabled daughter who would be screwed without her car so I know how valuable it is.