What the MOT data actually says about the work coming through your bay
DVSA publishes every MOT failure by defect category. We read the latest figures to show which repairs are most likely to be waiting on the other end of your phone.
You do not need to guess what work is coming. DVSA publishes MOT testing data for Great Britain as a quarterly statistical data set, broken down by vehicle class and by the category of defect that caused each initial failure DVSA, MOT testing data for Great Britain. It is free, it is national, and almost nobody in the trade reads it.
Roughly a quarter of tests fail on the first attempt
Across all classes in the first quarter of the 2025 to 2026 financial year, the initial fail rate was 26.80% and the final fail rate — which excludes vehicles that pass after minor defects are rectified at the test station — was 21.54% DVSA, MOT test results by class of vehicle. In diary terms, roughly one in four MOTs you book is a conversation about further work, not a certificate and a goodbye.
Where cars and light vans actually fail
For class 3 and 4 vehicles in the first quarter of the 2026 to 2027 financial year, the defect categories appearing in the largest share of tests were lamps, reflectors and electrical equipment (9.98% of tests), suspension (8.21%), tyres (6.55%) and brakes (5.83%) DVSA, class 3 and 4 initial failures by defect category.
The dangerous-defect split is where it gets operationally interesting. Tyres accounted for 62.69% of all dangerous defects recorded, and brakes for 27.15% DVSA, class 3 and 4 initial failures by defect category. Those are the failures a driver cannot legally drive away from, which means they are same-day work whether your diary agrees or not.
What we take from it
- Lighting and electrical faults are the most common failure category by share of tests, and they are usually quick, low-value, high-volume jobs.
- Tyres and brakes dominate the dangerous defects, so a share of your MOT bookings will need to convert into immediate work.
- A diary with no slack cannot absorb that, which is the practical argument for holding a slot back each day.
- The phone rings after the failure, not before it. Those calls are urgent and impatient.
A quarter of your MOTs turn into remedial work, and the most dangerous share of it cannot wait until next week.
How this changes how you answer the phone
If a meaningful slice of your incoming calls are urgent MOT-failure jobs, the cost of a ringing-out phone is not just a lost service booking — it is a lost same-day, higher-value job. Garage Ghost flags urgent language on the call to your dashboard and by SMS rather than trying to judge it, so you can decide whether to squeeze the car in. Set your ceiling first using capacity planning for a small workshop, and put your own figures into the missed-call calculator to see what those calls are worth.
One caveat, stated plainly: DVSA notes this data set is not classed as an official statistic, so treat it as a strong national indicator rather than gospel, and always sense-check it against your own bay DVSA, MOT testing data for Great Britain.
Published Sources & References
- MOT testing data for Great Britain(Driver and Vehicle Standards Agency)
- MOT test results by class of vehicle(Driver and Vehicle Standards Agency)
- MOT class 3 and 4 vehicles: initial failures by defect category(Driver and Vehicle Standards Agency)