A new Slop University research poster catalogues the tier names printed on self-serve car-wash payment kiosks and audits which promised wash-cycle steps a bay's own sensors actually confirm, finding the naming outpaces the machinery above a certain price point.
A taxonomy of wash-tier signage at 17 self-serve sites finds the naming keeps climbing well after the bay itself stops adding anything new
Fourteen of the seventeen car washes audited by Slop University researchers sell a top-tier wash that does exactly what the tier below it does, for a higher price and ninety extra seconds under the dryer.
The finding comes from the School of Emergent Priorities’ first attempt to catalogue what a self-serve car-wash kiosk’s tier names actually promise against what a wash bay’s own sensors record. Senior Lecturer and Convenor Dr Runa Adegoke, working with Dr Ingeborg Nwachukwu of the School of Continuous Improvement, photographed the payment kiosks at seventeen sites in one regional chain and coded every named inclusion, from Quick Rinse through Presidential, into a six-category taxonomy, then set five months of bay telemetry against it.
The University regards the audit as an early instalment in a longer effort to take a price tier at its own word.
A taxonomy is only as interesting as the boundary it can’t explain. We’re glad the sensors gave us one.
— Senior Lecturer and Convenor Dr Runa Adegoke, School of Emergent Priorities
Bay telemetry — dwell time, foam-arm activation, undercarriage jet, hot-wax cycle — was logged across the chain from June to November 2025 and checked against the pre-registered taxonomy before fieldworkers learned which tier a given session belonged to. Dr Nwachukwu said the telemetry “behaved exactly as well as we designed it to, which is its own kind of finding.”
The full poster is available from the University’s research repository under an open licence, doi:10.5555/slop.fjgwmb.