There's a very long list of inferior technologies that beat superior ones in popularity, or age. QWERTY keyboards, Electronic forms, Combustion engines, Agribu

There's a very long list of inferior technologies that beat superior ones in popularity, or age. QWERTY keyboards, Electronic forms, Combustion engines, Agribusiness refinements, Byte-oriented computers, Genetic technology (outside of GM crops), Building construction/insulation, Monorail and near-sonic trains, Pharmaceuticals, PlayStation, 8086, TDMA, USB, PHP, VHS... The most common link between them is a low barrier to entry, which has multiple facets. 1. Intellectual Property If you patent technology, it makes it hard or more expensive for others to license and/or implement it, which leads to a loss of market share unless you completely monopolize the market your product occupies. Any alternative technology which is both cheaper and more ubiquitous will dominate. 2. Cost More advanced technology is, almost by default, more costly. It is costly for manufacturers to develop a new process to manufacture it, it is more costly for developers to learn to develop new products that use it, and it is more costly for consumers to buy it, both because of the lack of manufacturers and developers for it. It also will inevitably require one to learn a new way to use it. 3. Doesn't address a critical need If there are two competing technologies, and both provide for the same need, the one that best addresses a need and costs less will win out. If one does not provide for a critical need, it will be left in the dust. Often that "need" is as simple as being faster or easier to operate, but it can also include specific functions. -- The earlier you are able to introduce a technology, and as long as a newer technology does not beat you on platform support, cost, and critical features, you will remain on top. Browsers are a good model for how this has changed hands over the years. The barrier for entry is smaller because you can make them for multiple OS platforms fairly easily, but sometimes one would have a monopoly. So to compete with the monopoly, one browser would remove a barrier to entry - cost - and develop new critical features. But then the other competitors could adopt the same changes and compete again. Another example is Intel x86. Intel tried several times to end the x86 product line. But as the industry refined standards around it, it became too expensive and complicated to try and introduce a complete replacement. It was even forced to adopt features that competitors introduced. UNIX (and C, since a lot of people lump them together) has stayed around so long because it has a low cost, low complexity, is ubiquitous, can adopt new features easily, and is highly compatible/portable. Even if you have a new critical feature, it can usually just adopt it. In the end, kernel design has nothing directly to do with how it is adopted by users. Kernel design affects how software developers, and later manufacturers, will use it. And that affects what is left for users to adopt. Nobody really notices a kernel; what they notice is the ecosystem.