There isn't always a 'why' that makes sense. A lot of ways in which things are done are determined by their history, not by what one would expect to work best.

There isn't always a 'why' that makes sense. A lot of ways in which things are done are determined by their history, not by what one would expect to work best. Moreover, business/selling is not an exact science, so you should not expect the salesman to provide reasons that make rational sense. So, from the other side of the fence, you need to make sure your engineers understand that.