It is not very scientific blaming the marques...
You could very well argue that people who buy cheap second-hand cars are not likely to willingly invest in the vehicle's servicing or maintenance.
If this assumption is correct, then this will see fast depreciating cars at the bottom of the MOT fail list, and slow depreciating cars at the top.
Of course, you could argue the opposite - that the MOT failing cars are crap and theretofore depreciate quickly...
And then this could be a compound relationship, where both assumptions are correct and this spirals the cars' value downwards and it deteriorates even faster...
What we need is a proper randomised test with a control group
(I studied this at Uni 30 years ago - experimentation and research methodology
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