The reality: Academic research to commercial product, part 2 - [tried and true]
The NRE for even a conceptually simple system (the car parking system) can easily be US $1 million or more. Development can take a year or more to complete the design and prepare for manufacturing, distribution, and installation. The NRE for a medical device or safety-critical system can easily cost more than US $12 million and take five or more years to complete. That cost represents only development up to the point at which one would be ready to manufacture, distribute, and install (or implant) products. Obviously, these numbers vary according to the project, but they do indicate that a lot of engineering and effort go into taking a proof-of-concept and realizing a commercial product that is ready for sale. If your proof-of-concept cost is US $50,000 to develop, then you have only realized 5% or less of the cost and effort required to render it a commercial product.