Imagine this year’s Spanish GP – a crash at turn one that means safety car, and then it starts raining. Let’s say one driver from each team pits. Which of the garage orders would be better for traffic?
It’s very likely the cars are more or less in the order of their car numbers (not exactly, but more or less – 1-10 will probably be ahead of 16-25). If Red Bull and McLaren are at the end of the pitlane, and they arrive in the pits first, they won’t have any traffic from the midfielders, as those will stop behind them. With usual order, they’d have to wait for midfielders to pass until they could be released, and then they’d have to watch the midfielders diving into their pit boxes.
Sorry if I complicated it (not my first language…), but I think it should be clear.