Gregg Williams, writing about the introduction of the Apple Lisa for the February 1983 issue of Byte Magazine, noted that when it came to a choice of an input device to use with the new computer’s graphical interface, the designers “passed over such devices as light pens and touch-sensitive video panels in favor of the mouse, a pointing device used in several Xerox PARC machines.”

Apple’s main refinement–not necessarily an improvement–to the PARC mouse design was only providing a single button. According to Williams, “Apple broke with the conventional wisdom of two- and three-button mice after user tests indicated the people aren’t always sure which button to push on a multi-button mouse.”