Progress is about eliminating all non-working solutions. These fell by the wayside

Ford Nucleon
There are many reasons the Ford Nucleon never caught on - but the biggest one is probably that the technology required to build it (a nuclear reactor small, light and stable enough to power a car) doesn’t really exist. Even now, 60 years on.

Mercedes air balance package
Usually it takes years for a car to develop that special whiff – not so some Mercs, which can be had with fragrance dispensers that pipe special scents into their leather-lined cabins. If this isn’t luxury, we’re not sure what is.

Sinclair C5
A lot of people think the Sinclair C5 was simply ahead of its time. Many others think it was just terrible. Essentially a battery-assisted tricycle, it was expensive, slow, quite dangerous and especially embarrassing to be seen on.

Built-in record players
To work properly, record players rely on, well, not being jiggled about while they’re playing. Legend has it that the ones fitted to cars in the Fifties were set to bite into the record a bit more firmly to stop them skipping, thus ruining the record after only a couple of plays.

BMW Z1's doors
We kind of wish this one had caught on. The now quite collectible Z1 is, so far as we can tell, the only car with doors that disappear downwards into the sill. And how stylishly. You could even do it on the move for, erm, reasons that must’ve been important at the time…

Fiat in-car espresso machine
Without the power, style or handling to keep you alert, Fiat were forced to look elsewhere to keep drivers of its 500L MPV awake. Hence this built-in coffee-machine – a feature which has appeared on precisely zero cars since. That’s not gone well.

Amphicar
Mostly, being on water is slower than not being on water. And you might sink. No real surprise then that amphibious cars haven’t flooded (ha) the market in the last few decades. Maybe we’ll change our tune when the waters begin to rise…

Honda WOW
Honda says WOW stands for ‘wonderfully open-hearted wagon’ – really – and that this 2005 concept was designed to be the most dog-friendly car ever. Much as TG loves its dogs, if owning one meant driving a WOW, we might have to give it a miss.

Automatic seatbelts
These things were vogue in the Seventies, Eighties and Nineties, while the American government was umming and ahhing about making them compulsory if a car wasn’t fitted with certain types of airbag. Luckily, they never made it across the pond.