In the late 19th century, the innovation around internal combustion engines and fuel injection technologies began. The technology proved the existence of a viable solution that could be applied to a number of fields. Transport was one of them. The inventors/innovators were tinkering with the engines, trying to find the most compact, lightweight, and efficient system. The viability of engine technology opened up possibilities of replacing horse-driven carriages with human-controlled automobiles. The earliest version of a finished, usable automobile was an engine fitted onto a two-wheeled (cycle-like) frame. This was called the riding car (see the following image):
An article about the car says, "The most important prerequisite for the riding car, simultaneously the world's first motorcycle, was Gottlieb Daimler's four-stroke, single-cylinder engine, which he registered for patent on 3 April, 1885. In the sum of its features, the riding car was the most important precursor to individual mobility, thereafter rendered possible by the advent of the automobile. It was proof on wheels that the internal combustion engine was capable of powering a road-going vehicle—and that a human being could fully control it."
The riding car was proof that a vehicle powered by an engine and controlled by a human was possible. The riding car had validated technology viability. It had cleared step one in the problem/solution fit stage from a technology perspective. Still, it hadn't yet shown the viability for the car makers who were competing with horse-driven carriages. This engine was still not viable for a four-wheel automobile. The target segment was quite different and the market needs of the target customers that car makers would go after was quite different. As Henrik Kniberg described, the riding car (two-wheeler) was the mvp for "human controllable automobiles." It proved that a solution for a problem worth solving existed. It also proved the technology viability.
However, there were quite a few other aspects to uncover for the car makers. Daimler and Benz's individual efforts in creating a three-wheel and four-wheel automobile respectively emphatically proved that the technology viability established by the riding car's engine could be applied to a different product with some modifications. There was a second wave of inventions and patents between the first riding car (two-wheeler) and the four-wheeled automobile (https://www.daimler.com/company/tradition/company-history/1886-1920.html).
The technology innovations in the engines proved that a human-controlled automobile was possible. Once the initial technology (of the engine) was proven to be viable, a host of vehicles started to sprout including motor boats, omnibuses, and cars. The power, acceleration, fuel material, and so on had a second wave of innovations that paved the way for a three-wheel and four-wheel version of the automobile.
The first wave of innovations and technology viability of engines proved that a two-wheeler automobile product was possible:
The second wave of engine and fuel injection innovations led to far wider range of vehicles:
The second wave of innovations proved that there was a possibility of manufacturing four-wheel automobiles for the people who were travelling in horse-driven carriages. The market was available and the technology was viable. The problem/solution fit had been established. Now the product/market fit had to be explored. When the first cars were made, they were competing with the horse-driven carriages. They were trying to fill a gap that horse-driven carriages couldn't meet: speed and safety. When motor cabs replaced hand-driven horses, the emphasis was on how much roomier the motor cars were and how much safer they were when compared to horse-driven carriages. The following article clipping shows this pitch:
Source: https://en.wikipedia.org/wiki/History_of_the_automobile#/media/
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