Selling open-hardware tools
A possible open hardware business model is to simply sell the product. Open hardware, or not, selling something may be the easiest way of generating income[@pearce2017Emerging Business Models for Open Source Hardware]. However, many open hardware projects focus on cutting costs, and this is a mistake. In many cases, lowering costs is associated to a lower quality. Being open does not guarantee being cheap, nor the other way around.
If the plan is to sell cheaper than the competition, the open nature of the project may just be a hindrance, since it is likely that bigger suppliers of parts won't want their designs becoming publicly available (this is the case of the Raspberry Pi, for example).
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