I was laying on the ground, watching a mechanic install a new leaf spring on the unbroken side, so that I would have a matched pair of brand spanking new leaf springs on my single axle trailer. I was at the business from which we had ordered and shipped the first leaf spring. It was quite a large business actually, with a 'reputation' for being experts.
If I learned to repair a broken suspension part in the field, it might someday save me hundreds of dollars in towing, if the towing service balked at paying the tow truck to come to an inaccessible location. (Be aware that towing insurance is not a panacea. There are reasons why you don't want to camp in too backwoodsey a location.)
In fact I did learn a couple tricks of the trade before the manager came over to inform me that insurance regulations did not allow a customer in the work area. In fact, I had already thought of that, by laying down just outside the building. (My head wasn't underneath the trailer.) Nope, that wasn't good enough. He quickly shuffled me off to the customer's lounge, where there was the usual television playing daytime shows, and a variety of trashy glossy magazines.
Insurance regulations, eh? Well OK, but there are other reasons, too. Nothing is more irritating to the office types than a customer who wants to talk to the mechanic. In part, this is just marketing psychology. Any kind of repair facility, including a doctor's office, benefits from an aura and mystique when the customer drops off the problem, leaves a four word description of the symptom, the office-type (a glorified college-educated clerk) spends a half hour doing paperwork on a computer, and then at the end of day, the repaired item magically appears.
The more ignorant the customer stays, the more magical the whole process appears, and the easier it is to swallow the astronomical repair bill.
In my case, the first thing the mechanic did was jack the trailer up by the flimsy steel cross-piece. That is a classic no-no. One should always use the heavier frame that runs along the long axis of the vehicle. Seeing the mechanic make that mistake caused his aura to pop instantly. This single observation means that they lost my business. Back at the small town where my original spring broke, the mechanic mentioned that he wouldn't use the flimsier steel cross-piece. He has won my business in the future.
But the disappointment at the big firm was more general than that. Rather than describe it in detail, let me insert a pertinent quote from Matthew Crawford's book, "The Case for Working with Your Hands."
Consider the case of a man who is told his car is not worth fixing. He is told so not by a mechanic but by a clipboard-wielding "service representative" at the dealership. Here is a layer of bureaucracy that makes impossible a conversation about the nitty-gritty of the situation. This man would gladly hover around the mechanic's bay and be educated about his car, but this is not allowed. The service representative represents not so much mechanical expertise as a position taken by an institution...
The example I have given shows that there is a certain rational self-interest on the part of the institution to separate the customer from the mechanic. But I don't like it anyway.