My final example of bad pliant response are rollovers that invert or otherwise drastically change the original image. One of the subtle cues of visual interface design that made the original Macintosh interface so usable was its consistent implementation of buttons inverting upon mouseclicks. When users click on a button in the Macintosh interface, the button inverts and appears to be pressed. Many websites have buttons that invert or appear to be depressed when the user simply rolls the mouse over the button. Windows, and other operting systems also use the same system of color inversion and simulated depression to indicate that buttons have been clicked.
Users already expect that kind of response, and most websites and browsers can easily support it.
My preferred method of following my guidelines begins with a distinct button design that is clearly labelled. That fourth state allows the menu to remain a constant shape and in the same position from page to page, and separates the active page's button from the other clickable buttons. If a description of some kind seems necessary, use link titles instead of a complex rollover that displays a graphic description. Link titles will more naturally blend in to the interface of both the browser, and the operating system, if the designers of the browser have done their job correctly. Some websites have been using on-mouseover underlining of links as a form of pliant response.