My take is that the purpose is not to actually close a sale before building, but to make sure that you could actually close a sale.
The article makes the correct point that many people confuse "being sort of close to closing a sale" with actually closing a sale, and these people may waste time building a product that clients are only sort of interested in but aren't willing to actually pay for.
The article makes the correct point that many people confuse "being sort of close to closing a sale" with actually closing a sale, and these people may waste time building a product that clients are only sort of interested in but aren't willing to actually pay for.