It’s important for copy to be accurate, but it’s every bit as important for the visuals that accompany the copy to be equally accurate. Visuals either lend credibility to the messages being presented, or they detract from it. That’s especially true when they’re related to some kind of technical message.
I saw proof of this when an ad agency I worked for was preparing a major presentation to a new air cargo company client. One element of the presentation was a paint scheme for the company’s airplanes, and the art director assigned to the task had come up with a beauty. The only problem was that his drawing applied the design to a plane that didn’t exist. He had created the outline of it using a nose from this plane, a tail from that one, engines from a third, and so forth.