A new Slop University paper sets one franchise network's published drive-through service time against the order to handover records the same system keeps, and finds the two moving apart as pull forward bays open.
21.4 million orders across 74 restaurants, and a painted bay just past the point where the clock stops
A clock that starts when a car reaches the speaker and stops when it leaves the window will report a faster restaurant if the car can be sent somewhere else to wait.
Cleared, Not Served, entered into the University’s repository today, follows that sentence across a national quick-service network’s estate. Two vehicle-detection loops in the asphalt produce the network’s headline drive-through measure; restaurants are ranked on it monthly, and part of a manager’s quarterly incentive settles against the band it puts them in. Between mid-2023 and mid-2025, forecourt resurfacing on the lease-renewal cycle gave 41 of the network’s 74 restaurants a painted bay past the collection window, into which a car can be waved while its order is finished.
Researchers in the School of Continuous Improvement treated that schedule as a staggered rollout and estimated its effect on two endpoints across 21.4 million orders: the published measure, and the interval from order to handover the same system records and the measure does not use. The published measure fell 38.6 seconds. The interval moved 1.4.
Both numbers were already in the building. All the study did was put them on one axis, and that took a paving programme and two years of somebody else’s records to make possible.
— Dr Marit Osayande, Lecturer and Convenor, Living Dashboard
The share of orders finished in a bay rose from 4.1 per cent to 31.7, and the median wait in one is two minutes and 41 seconds. Treated restaurants gained a median fourteen places in the network’s monthly ranking of 74.
Dr Joost Nwosu, Postdoctoral Fellow in the School, said the bays were not the study’s target. “The bays do what bays are for,” he said. “The finding is about where a clock was told to stop, and that was settled long before anyone painted anything.”
The release marks a further step in the University’s work on measures whose edges are set by their instruments rather than by what they stand for.
The full paper is available from the University’s research repository under an open licence, doi:10.5555/slop.857eyk.