Auto repair, the basic primer
An assurance of quality is the second reason. Chains make certain that all their mechanics are licensed and certified. On top of that, having more mechanics at the shop means having more experience on hand to puzzle out obscure problems, and means it is more likely that you will get the services of someone who specializes in your car's type of problem. Convenience is the third reason. The warranties that independent mechanics offer on their car repair are generally good only at their own shop.