Two MoTacon attendees are on the left. The MoTaacon logo is in the center, and to the right a prompt to Get Your Ticket.

Car Wash Test

Car Wash Test image
If you ask an AI model, "I need to get my car cleaned, and the car wash is 100 metres away, should I walk or drive?", several popular LLMs tell you to walk. They give you a well-written breakdown on saving petrol, squeezing in a quick bit of exercise, and avoiding the hassle of starting an engine for a short trip.

It sounds sensible, until you remember the physical reality: walking 100 metres leaves your dirty car sitting in the driveway.

The model isn't reasoning. It catches keywords like "100 metres", "walk", and "drive", and immediately routes down a path of health and environmental advice. It completely misses the actual goal because it lacks a basic mental model of how the physical world fits together.
Explore MoT
MoTaCon 2026 image
Thu, 1 Oct
A tech conference to help you navigate the ever-shifting landscape of Quality Engineering, AI, Leadership, Product, Accessibility and Security.
Advanced prompting for testers image
Advanced prompting skills to turn AI into your trusted testing companion.
This Week in Quality image
Debrief the week in Quality via a community radio show hosted by Simon Tomes and members of the community
Subscribe to our newsletter