This has always been true. I never fixed my car. I knew how it worked well enough to know, hey, that sounds like its coming from the exhaust pipe. Then I took it to the mechanic. I can do basic maintenance on my bike, but I still take it to the bike shop. I have a small collection of vintage cameras, which means tracking down the few people left who know how some particular model works, might have parts. If your Synchro-Compur shutter needs parts, forget it. For most people, most of the time, the assumption has always been that someone else knows how to do that.