Engineering any one part is tough. Engineering 10,000 parts to work together is much tougher.
I was blessed to start out in the auto business. First, there are no excuses, those cars have to go down the line on a certain date and there just is no delaying the design or postponing the release.
Another great thing about automotive engineering is how tough it is. Hot cold noise vibration, and everything had to be dirt cheap. Just as valuable, you have to understand configuration management, Ford had 19 truck assembly plants, and you had to plan every design revision and its phase-in carefully.
A good system design is like a well-rehearsed orchestra. A lousy design is, well, lousy. There are just so many things that go wrong in a system. And its not just that it works on the lab bench. It has to work and fail gracefully and be easy to fix or recycle when its broken.
A lone wolf can design a component, system design is a social endeavor.
A complex design has complex interactions. Back when designs were done on drafting tables its amazing that anything fit or worked at all. CAD (computer aided design) has made things much easier.