I think the Ford Edsel (named after Henry Ford's son) comes pretty close to the top of the all-time worst car list.
Went like, and sold like, a lame duck.
And then there are Rovers (at least from 1980 onwards).
I had a Rover 2000 which had electrics that'd cut out just at the hint of a rainy weather forecast.
Just cut out. Dead as in parrot.
Which meant the engine went. But the worse thing was the power steering went too.
Great fun when cornering and you suddenly have no power and a dead steering wheel that doesn't do anything. Loved that car so much I paid to have it carted away.
And another thing! Rover 200 series (at least mine) had this endearing habit of disliking right hand corners.
Take a right hander and sometims (not always, that'd be too easy) the power just went. No steering. Nowt.
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Then it decided to branch out and took a spasmodic dislike to left hand corners.
So, really brilliant, I ended up in London (where corners are a bit frequent) with a car that only really liked going in straight lines.
No wonder Rover are no more. Mind you, the old Rover 90s - brilliant cars.