Ford GPA

The amphibious jeep is here as the honest counterexample. About 12,778 were built in 1942 and 1943, but the Seep sat lower in the water than its designers intended, could not safely carry much cargo, got very wet in a chop, and its bilge pump could not keep up in moderate seas. It was far less successful in military service than the DUKW. It still proved something. Surplus examples went to farmers, ranchers, hunters and campers, one was rebuilt as Half-Safe and driven and sailed around the world in the 1950s, and the Soviet Union copied the idea after the war as the GAZ-46, which began production in 1952 and was a much better amphibian. A flawed design that taught others how to do it right.