Summary: The movement time to a target depends on the size of the target and the distance to the target.
Paul Fitts was one of the first psychologists who understood that human error is attributable to poor design as opposed to just human fallacy. He studied airplane-cockpit design during World War II and argued that many losses that had been attributed to human error were, in fact, due to poor design.
In the 1950s, he became influenced by the Shannon’s famous information theory. Like George Miller, who applied the concept of channel capacity to human memory and, in the process, came up with the famous magical number 7 as the bandwidth of human