When taking your school bus to a reputable repair shop, they will perform inspections of each item in a preventive maintenance (PM) checklist. This is more than just looking at components. They will pay attention to the little things, the little problems, making repairs to the smallest of defects.
In doing so, the larger potential problems will be repaired and never develop into real problems. Some technicians focus on the problem at hand, fixing items that have failed, but they fail to repair the cause of the failure. This causes repeat problems. Each problem has a cause. Finding and repairing the cause prevents future problems from occurring.
A PM checklist should be organized in a systematic method that is meant to be followed in order from top to bottom. In doing so, an organized routine will be developed and remembered, and the technician will get better and faster at it as time goes by.
The school bus drivers will appreciate a job well done even if it takes a little longer. They will appreciate not having to drive an old spare bus repeatedly.
Doing it right the first time increases reliability and — most importantly — safety.