Ability to accelerate, steer and stop – Running your car with worn tyres makes it much more difficult to accelerate, steer and stop which puts you, your passengers and other road users at risk.
Fuel consumption – By increasing drag on the road, worn tyres will consume fuel inefficiently and cost you more to keep the car running.
Aquaplaning – Worn tyres decrease tread depth which means water is dispersed less effectively. In poor conditions this can lead to tyres losing contact with the road surface/aquaplaning.