Designers should draw, I think. I know a lot of people become designers instead of artists because they can’t draw or they don’t want to, but in my experience as both designer and artist, drawing is necessary to both disciplines.
How can one express an idea to another except through drawing, or at least doodling? Sure, the idea can be expressed in words, spoken or written, and we’ll use a lot of words to convey the idea and also leave a lot of room for varied interpretations. The espression is much more succinct in a drawing.
Drawing is a visual language. Like any language, it can be learned, and some people are much more adept at learning it and using it than others. And, as in learning a language, if you don’t use it you will lose it.
The other thing about drawing that I find to be true is that it is evidence of thinking. In looking at sketchbooks of great masters (DaVinci, Michaelangelo, Rodin, etc.) what they were envisioning was recorded on paper. And in teaching I find students are able to express their ideas quite easily through doodling, drawing and cartooning. I can see what and how they are thinking and if they are thinking adequately to deal with the entire design project.
I keep a sketchbook. It’s full of serious drawings, doodles, gestures and words. In my business I carry a daybook instead of a PDA because I can put pen to paper and doodle while recording information. I do this especially during phone calls, and my notes weave in in between my quick sketches and doodles. It’s difficult to draw on a PDA, I’ve found, and far less satisfying than the tactile sensation of placing a pencil against paper.
I will always draw, doodle and sketch.