As someone who knows their way around an engine bay, and has done jobs wrong enough times to learn a thing or two, I am always curious to know what other people think about when they think about reliable.
Personally, I don't consider reliability never opening up the hood of a car, never checking brakes, or never investigating that new noise. Just this morning I checked the oil in the MS3 while getting fuel because I know it's an 07 turbo car and is known for oil consumption. It was fine, just like it was last time, but if I didn't check it, and it wasn't fine, and the engine ate itself because the turbo seals failed, I am positive someone would consider the MS3 unreliable. In fact, the Mazdaspeed community is full of people who don't pay attention to their vehicles, and get pissed off when they load the stage 3 Cobb tune and nuke their otherwise factory motor. It's altogether considered a platform full of problems, but almost all of them can be attributed to failing OEM parts due to age or mileage, or owners modifying their cars outside of their means.
My previous car, the '10 DSG Passat, took some work to revive, but in the end, was just as reliable as comparable Japanese cars. Yes, it was built different, but after learning the quirks about how and why things went wrong, it was a dependable family hauler that didn't mind getting wrung out every once in a while despite it's size.
I fixed my gas hot water heater this weekend, mostly just cleaning some components up and everything is back behaving as it should. I could have just as easily replaced the entire unit. Or called an on site repair company. Some may argue that would have been a better option, as I did spend an hour of my time doing the work, and people like to make the argument that your time is worth something (true). But, my Son and I did it together (he's 4), and no, he isn't going to go do the job on his own, but he was curious, and helped in his own way. Would I consider the hot water heater a failure? Has it become unreliable since it needed attention from years of 24/7 use?
It seems that we have gotten to the point where every mechanical or electronic device is just assumed to never need attention, that everything is solid state, and never needs a look "under the hood".
Reliability to me is the continuation of functionality with attentive maintenance or replacement of supporting components. An object is a sum of it's parts. My MS3's suspension isn't problematic because I had to replace the sway bar mount bushings, it's just necessary. My Passat's need for a front cover gasket to fix it's misfire doesn't mean it was designed poorly, it had 190k miles and was at the end of it's service life. My hot water heater isn't garbage because I needed to clean up the components in the burner chamber and vacuum out the intake screen, it's just needed.
We're "probably" all a bit different than the usual consumer, in that we understand that most machinery needs to be maintained and serviced, but it's disappointing to see more and more of the online communities shifting towards negative commentary on a given vehicle. I truly miss the "good old days" of the plethora of forums (think early 00's MR2OC days) where there was as much positive dialogue as diagnostic help requests or troubles. GRM excluded of course, this is a great forum and I am very happy it's here.
Maybe this is more of a commentary on our consumer culture, the idea that if your performance car wipes a bearing it must be time to part the whole thing out and scrap the shell. Or that a lot of cars are designed to be "off limits" to DIY'ers. Or that by consistent marketing the goal is to remind us and our kids that this new thing is out and it's absolutely going to make our lives better and you really shouldn't bother repairing that old one.