One case not covered, I believe I saw at London Heathrow was where 4 cars essentially moved people across only 2 floors. With only 1 centralized button, only 1-point-something car was effectively moving people on average, because people had to wait for the currently filled car to have its doors closed and starting to move, before hitting the button to call the next car to pick them up. Imaging 100-200 people in line and, often, overly eager would-be elevator passengers hitting the button too early. Thus leading to halting the just filled car and doing an additional full open and close doors cycle. Fun stuff!