Inventions can certainly be a great way to start a business, however most inventors never get past the invention stage. Once a prototype has been made it is important to apply for a patent to protect your invention. In addition, a market study should already have been done to test for the viability and market size. Does the invention fulfill a need not currently handled? Is it an improvement on current products, etc. Inventors need to take the necessary steps to protect and then manufacture, or license out the manufacturing and market the invention and not let it be just another good idea on the shelf.