In any case, it's good to have a mechanic, before or after the malfunction. A mechanic occasionally inspects a vehicle when you have a suspicion that something is wrong, or when you experience a malfunction, you can choose a good mechanic to repair it. However, it is better to choose a mechanic before the failure, because he can prevent it, and so, possibly, you can avoid a malfunction. If the malfunction does occur despite the selected mechanic, he still knows your vehicle better than a newly-selected mechanic. In addition, long-term acquaintance with a selected mechanic means a better approach in reviewing and repairing your vehicle.
So, your statement is true.