What is the final factor in determining whether a vehicle will stop?

The final factor in determining whether a vehicle will stop is the contact between the vehicle and the road through the tires. This is crucial because the tires provide the necessary grip and traction needed for effective stopping. If the tires are worn, under-inflated, or otherwise compromised, their ability to maintain contact with the road surface is diminished, leading to increased stopping distances or a complete failure to stop.

While the weight of the vehicle and the braking system both play significant roles in how quickly a vehicle can decelerate, they are not determinants of whether or not the stop can ultimately be achieved. The distance from the stopping point becomes relevant only once factors like weight, braking, and tire contact are established, as it is the effectiveness of the tire-road interaction that will principally dictate the vehicle's ability to come to a halt in time. Therefore, the state of the tires in relation to the road surface directly influences stopping ability, making it the final factor in this scenario.