What factor is contributing to the labeling of a vehicle as unsafe?

Labeling a vehicle as unsafe primarily hinges on the condition and functionality of its components. When there is defective or malfunctioning equipment, such as brakes that do not respond, lights that do not work, or tires that are in poor condition, the vehicle's capability to operate safely is compromised. This directly endangers both the occupants of the vehicle and other road users, leading to a classification of the vehicle as unsafe.

Defective equipment is an objective factor that can be measured and identified, such as through a pre-trip inspection, and is a determinant of whether a vehicle can be deemed fit for the road. Other factors like a driver's behavior, weather conditions, or visibility are situational and may change frequently; they do not intrinsically indicate the safety of the vehicle itself.