Every car fails its MOT more often as it piles on the miles. Here is the whole 340-model fleet, and you can drop any model in to see how its own curve compares with its class.
First-time MOT failure percentage, 2025 data. The fleet line is the weighted average across all 340 models; a model's own line is drawn only where it has enough tests at that point. Each picked model gets its own colour and dash pattern; its class average is the dashed grey line behind it.