The copy itself shouldn't dwell on the pain. After all, the audience already knows its pain. Instead, the piece should quickly get to the real point how the product or service solves the reader's problem. The purpose of the piece is also a key to determining what type of information the copy should include. If the piece is meant to be a leave-behind after a sales call, the copy might summarize the main sales points brought out in the presentation.
White papers spell out all the details.
A white paper for a business audience will often provide in-depth descriptions of the business problem, the requirements for addressing that problem, and often how the product or service meets those requirements. A technical white paper might provide an in-depth description of product features. An advertisement designed to create awareness, in contrast, might provide just enough information to get prospects coming back for more information when they're closer to making a purchase. The positioning and messages are the heart of any marketing piece. These determine its content, including the key benefits the piece will highlight, as well as proof of those benefits.