My talk would often go something like this:
Entering the elevator – So, what is print manufacturing all about? Well, imagine the printer as a lumber mill – a very special lumber mill. This is a lumber mill that doesn't govern what logs are acceptable for processing. Imagine that the logs were sometimes solicited by sales people and at other times by artists and other creative types. You'd receive anything vaguely shaped like a tree - dead wood, rotten wood, green twisted wood, phone poles, and non-wood poles painted to look like trees. Before you were allowed to process the "logs" you would have to win a competitive bid based on your ability to deliver the finished wood products - without actually knowing what your customer understands by the term "finished wood products" nor which of the possible variations on a log you will be receiving. To help communicate with your customer, you would use a "proof" – a simulation of the finished wood product that you will deliver. Of course, the proof simulation of your products actually uses another lumber mill's equipment but at least it consumes a copy of the "log" your customer has supplied to you. Unless, that is, the customer-supplied log breaks the equipment and doesn't actually get processed. In which case you either return the log to the customer to be rendered more log-like or you take on the task yourself without actually being able to charge for the log refining service.
What we do is supply those special lumber mills (read: printers) the tools to make the incoming "logs" (read: files) more log-like as well as the equipment to process the logs into acceptable finished goods which the lumber mill will be able to deliver at a profit margin sufficient for us to extract a small but valued portion.
Ah! This is our floor. Be seeing you. :-)