What must a driver do when leaving the vehicle, even for a short time?

When a driver leaves the vehicle, even for a short duration, it is essential to turn off the engine. This practice contributes significantly to safety and environmental concerns. Turning off the engine prevents the vehicle from becoming a potential hazard; for instance, it helps avoid the risk of the vehicle rolling away if it's not properly secured and reduces the chances of an accidental fire. Moreover, it minimizes exhaust emissions, contributing to better air quality.

While other actions, such as locking the doors, may be prudent for security, they do not address the critical need to ensure the vehicle is not left in a potentially hazardous state with the engine running. Thus, turning off the engine is not only a responsible action but also a legal requirement in many jurisdictions when the vehicle is unattended.