To me that makes them part-hangers, not mechanics. Suspension/steering isn't like a misfire, where 20-30 different sensors, other parts, and wiring can be the cause, and even the pros can get stumped sometimes. A professional, experienced front-end guy will usually always diagnose correctly the first time. And if something still isn't right after the repair, he will pick that up during the test drive. A real pro won't let the vehicle go until it's fixed correctly. Find someone who knows what the heck they're doing and get the job done right.