One in the afternoon is the peak of the food delivery day. Volume is concentrated enough into this single hour that the difference between requesting a meal at five past one and at half past is measured in a genuinely different wait, and every rider in the city is moving at once.
Schools begin releasing their younger year groups around this part of the day, so the residential roads see their first afternoon wave. In many households the countdown to one o'clock is set by whoever is not doing the collection, as the reminder to leave.
On a Friday the same hour is the emptiest of the week: the working day has ended, the congregational prayer is under way, and the main roads clear for half an hour in a way they do at no other time. The countdown resets every twenty-four hours.
Common questions
Why is food delivery slowest at 1 pm?
Because demand is concentrated into that single hour more heavily than at any other point in the day, including the evening.