What should be checked on vehicle doors?

When conducting a pre-trip vehicle inspection, it's essential to ensure that vehicle doors are in good condition and function properly. The primary focus is on the operational aspects of the doors, which include checking that they are not damaged and that they open and close smoothly. This is crucial for safety, as doors need to function correctly in order to allow for safe entry and exit from the vehicle. If the doors are damaged or do not close properly, it can lead to serious safety issues while operating the vehicle, including the risk of the doors unintentionally opening during transit.

Although painting and the sound of the doors when closed may have aesthetic implications or indicate back door sealing, these factors are not the primary concerns during a pre-trip inspection. The statement about mirrors is also unrelated, as mirrors do not pertain directly to the condition or operational integrity of the vehicle doors. Thus, ensuring that doors are undamaged and operational is a vital part of the safety checklist before beginning a journey.