Ha ha. I once worked on a team where the "sales" people made a "partnership" with a famous company. We paid the famous company for this privilege and were able to advertise that the famous company used our product. We also agreed to do custom work on the product for the famous company for free. As part of the agreement, the "sales" people signed a contract that said that we would pay a huge penalty if we didn't deliver a certain piece of functionality in a certain time frame. After the developers discovered this, the "sales" people were informed that the functionality was impossible (as in it is a generally unsolvable problem).
Interestingly, when it all went bust, the company laid off all the developers and retained the "sales" people in the hope that they could somehow get some revenue flowing in. Not so funny at the time, but pretty hilarious to think back upon now. It has certainly shaped the kind of questions I ask when I interview for positions ;-).
I remember working for a dev shop a decade ago where the sales people would sell anything before even asking the developers if it was possible. If they were ever met with a "that's technically impossible with current technology" the response was usually an inspirational quote about finding the answer followed by walking out the door.
A good salesperson not only sells the product but also an idea. This way one can get a customer partially pay for the development of the final product bringing important source of financing.
Having a good salesperson is very important even if the product is not yet ready. A sales
The basic problem is that very few customers that can really benefit from a product actually make the effort to find the product. I sell a product that is vastly superior to all other solutions, yet almost none of my customers come organically via a Google search despite being number 2 in the niche. Almost all our new customers come indirectly after losing a contract against a competitor using our product. I have to say that this is the best way to sell.
The purpose of marketing is to generate demand, not sales.
This means that marketing is supposed to get a product on your radar, explain to you how it can help you, and then capture some vital information from you - say, an email address or a phone number.
THEN the sales team can swing in and push you the product.
Interestingly, when it all went bust, the company laid off all the developers and retained the "sales" people in the hope that they could somehow get some revenue flowing in. Not so funny at the time, but pretty hilarious to think back upon now. It has certainly shaped the kind of questions I ask when I interview for positions ;-).