Its not a direct comparison, but having owned cars from Japan, the US, and Germany, watching the videos of cars being made by the major manufacturers makes the difference somewhat obvious.
I've linked them below, but just looking at the factory processes, the workers, and the methods used it seems the German process is just designed to build cars with tighter tolerances. The cars don't move down assembly lines with humans touching them (in the 911 factory). When a human is working on the car, the car isn't moving. Compared to the Corvette (much cheaper, but still "high end") you can see how quantity is prioritized, and how the car never really stops for any extended period of time, before moving down the line.
Again, this is a totally subjective opinion, but comparing my current car (VW) to a similarly priced Ford I test drove the other day (GT350) the difference in build quality is night and day.
German cars tend to be less reliable than Japanese ones, as in this survey, possibly due to those tolerance. My 2018 German car feels a lot nicer than a 2018 Toyota, but has already had more problems, too. :|
Sometimes I wonder if the US auto industry suffers a bit competitively vs Germany and Japan due to a higher amount of "brain drain" to other higher-paying forms of STEM jobs in tech.
And historically when the Japanese _have_ gone overboard on tech, back in the bubble era, they also tend to back it up with overengineering.
Think of the fourth-gen Toyota Supra or any version of the Nissan Skyline GT-R. Or the Toyota Soarer/Lexus SC, which was basically a detuned Supra packed with luxury equipment and unique styling. They were technological marvels whose engines were overengineered beasts that could take ridiculous amounts of abuse.
At one point when my father was restoring a Mk 3 Supra, I got a look at the traction control boards since he had pulled one out to fix it. I was surprised at the lack of surface mount components, only to have my father point out the board had been made in 1989...
The Supra was a fundamentally ahead of its time design. Not without flaws but definitely pushing into new territory.
Maybe I misunderstand what you meant - but there were SMT components in 1989; indeed, some of the earliest examples of SMT can be found far earlier (late 1960s for example).
The reason it was likely thru-hole construction probably had more to do with reliability, as SMT work is more prone to damage from vibration (mainly), unless properly potted or conformal coated (and there may have been issues as to why they couldn't do that, either).
That said, consumer-level use of SMT components didn't really start until the early 1990s - but examples of earlier use do exist (for instance, one of my floppy drives off my first computer in 1986-ish had SMT components on the controller board - but it was still mostly thru-hole construction).
The 2JZ engine was one of the best (as in, most durable) engines that Toyota ever produced.
The sheer number of Supras, Lexus IS300s (1st generation), and GS300s that are still running today, most with over 200k miles, is a testament to the amount of over-engineering that went into that engine.
And then there are the crazies who took the NA version and added turbos...
A lot of E46 M3s are still running around with 200k on the clock despite having motors and chassis that chew themselves up. Same with the MK3 Supra and its headgaskets. IMO whether you still see cars around is as much a function of their value retention as it is of their robustness.
Of note - I think the Porsche factory built on Japanese (Toyota) innovations on manufacturing. I recall reading something about in the '90's, Porsche and VW were in a bit of a crisis in terms of manufacturing, cost of manufacturing, tolerances of manufacturing, etc. Turns out a lot of steps relied on a person hand fitting something or reaching into a bin of parts, etc. They hired Toyota to consult and rejigger everything. This was also when they came up w/ the Boxster, and then their SUV's to save the company as the 911 was definitely not paying the bills...
Took a lot of concepts we take for granted today, put them together to build "lean" manufacturing; also loosely inspiring modern agile/kanban software development.
Last time I checked, everything was an optional extra in 911s too. Even stuff that is a standard feature on cheap econoboxes. Last I looked there was something utterly bizarre as an expensive optional extra, it was something like powered windows or remote locks. Something that I didn't even know didn't come as standard in a car. I wish I could remember what it was. (this was like 2010, so whatever it was might have changed, but it was still grossly out of place back then. It was not air conditioning, that at least makes sense from a weight perspective on a performance car.)
If anybody thinks the difference between major brands is due a difference in factory processes they would be very wrong. The reality is every large manufacturer now has a culture built around Six Sigma/Lean/6S/Continuous Improvement/etc. Vehicles aren't manufactured in underground hideouts of secret societies. If a process if found to work well in one corner of the industry it absolutely permeates to other parts.
I agree that those methodologies have permeated the automotive industry. But does that mean that all automakers are utilizing them to the same degree of effectiveness? Anyone who's worked in a dysfunctional "agile" environment has experienced the danger of cargo-culting in methodologies that have proven effective elsewhere.
I've also always noticed American factories seem okay with workers showing up in whatever they want - i.e. you see in that video they are wearing their own t-shirts. To me this shows a lack of seriousness and pride in the work and team unity. It also shows a lack of respect for safety workwear and process. It shows the employer is likely cheap, and doesn't want to pay for workwear, and furthers my impression that they view their workers as disposable. IMO, it looks absolutely ridiculous how in the Corvette video one guy is wearing basketball shorts and Vans and the woman next to him is wearing a different T-shirt and jeans. Compare to the harmony shown in the German video. Please don't try to tell me that individuality is important in a vehicle assembly line!
I've linked them below, but just looking at the factory processes, the workers, and the methods used it seems the German process is just designed to build cars with tighter tolerances. The cars don't move down assembly lines with humans touching them (in the 911 factory). When a human is working on the car, the car isn't moving. Compared to the Corvette (much cheaper, but still "high end") you can see how quantity is prioritized, and how the car never really stops for any extended period of time, before moving down the line.
Again, this is a totally subjective opinion, but comparing my current car (VW) to a similarly priced Ford I test drove the other day (GT350) the difference in build quality is night and day.
This is a Porsche factory, building an expensive, high end 911 - https://www.youtube.com/watch?v=BbcKZ1lRDuA
Here is the Chevrolet Factory building a Corvette - https://www.youtube.com/watch?v=9ccOrwFs3No