Maybe it's not common wisdom in general, but it is a pretty common viewpoint in the startup world. Building products is expensive, and startups can't afford to build something no one wants. It's pretty much universal advise that finding an initial market fit should be the first priority of any new startup.
Literally making a sale before the product exists is the extreme end of that philosophy. Whether or not this is good advise, or even possible, probably depends a lot on the domain. For most domains though, there is some degree of market research that can and should be done before investing in product development.
Literally making a sale before the product exists is the extreme end of that philosophy. Whether or not this is good advise, or even possible, probably depends a lot on the domain. For most domains though, there is some degree of market research that can and should be done before investing in product development.