As revision projects begin, the product appears twice on the perceptual map, once in black, indicating its present position, and once in magenta, indicating where it will be when the revision concludes.

Among other factors, the time the revision takes depends upon the distance the product is moved on the map; the farther the move, the longer the project.

As more projects are added, the extra burden puts a strain on R&D which increases the time needed to complete each project.