The self-leveling hydraulic suspension in the W123 wagon was also a complication. The climate control system was failure prone, but failed in a sensible way--when the control unit failed it would no longer maintain a set temperature, but would still work as an open-loop system. The cruise control "computer" (completely analog device) was also prone to failure. But the thing is all that stuff was implemented simply, reliably, and with an eye towards service and maintainability. Maintaining the systems on a W123 was easy. I did it for almost a decade. It was a fancy car, but in a sensible high-quality way. It was built to be understood. There were excellent printed, bound shop manuals. It was obvious that an immense amount of thought went into the UX of working on that car. It wasn't just a luxurious car to drive it was also a luxurious car to maintain. Even the fucking hose clamps were special.. like, they had a continuous metal bearing surface so they don't cause pinch points and raised bosses for the worm gear threads to ride on instead of the punched slots you commonly find. Contrast that with the situation today. Everything was a lot better before corporations started using software as a wedge to separate users from real, meaningful ownership of their machines. It didn't have to be like that, they could have done it differently. Software could have been a wonderful thing for the automobile, but the way they chose to do it made it awful instead. And now everything is an iphone app with subscriptions and in-app purchases and engagement metrics. It's disgusting what these people have done to the world.