General Motors’ most prestigious division, Cadillac, claims to have coined the term ‘convertible’ in 1915 and emphatically planned to be the last US manufacturer to make one. The 1976 Eldorado was billed by its maker as:

…last of a magnificent breed. The Eldorado convertible. Today an extraordinary luxury car…Tomorrow a classic. For this is more than one of the finest convertibles ever built. It is the only convertible now built in America. And it will be our last. The very last. Because the Eldorado convertible will not be offered in 1977…

Convertibles, of course, returned (in 1984), once crash-safety standards had been advanced. As for the Eldorado name, that lasted for 50 years and a nominal 10 generations!