For example, many objects of interest in direct manipulation systems are not immediately visible. Menus must be pulled down, and files scrolled. Some of the needed information is obscured by other information. In addition, not all direct manipulation systems have rapid operations - commercially available systems in this category have had both slow and fast response times. The description of direct manipulation systems also appears to encompass very different types of systems.
Many interactive systems use an eclectic mix of styles.
The example of MacWrite 2 on page 93 is used to show a pull-down menu and thus is included in the chapter on menus. Yet, it is a display text editor and as a result could be classified as a direct-manipulation system. But such action seems inconsistent with the view of the menu user as reactive. The more we consider real world examples the more it becomes clear that the terms command, menu, and direct manipulation do not apply to systems as wholes. Systems, whether well designed or poorly designed, are mixtures of styles.