Does it count as a lemon if it ran well for a decade straight?
In my car-owning experience, yes. I've never owned a car as new as Bear's Jetta and I've only owned consumer cars with less miles on them for about 10k miles.
In other words, cars are usually the age and mileage of hers by the time I get them. It looks like she's spent more on repairs for that car than I have on purchasing and repairing the two cars I've owned. I don't have any repair horror-stories over $500. She's also got a few getting marooned horror stories, while I've never been marooned. Wait, that's not true. I had the battery go dead in that Mazda a couple of times, but I was marooned at my own house. Does that count?
Anyway, from where I'm sitting she had some unusually high bad luck with that particular car and that's what I call a lemon.
ETA: Sorry to drag this off into what may or may not constitute a lemon when you're looking for advice. To echo previous posters, the best advice I have is to look at used cars that are at least 3 years old. The depreciation really starts to slow down after 3-4 years. When you test drive those cars, take them to a trusted mechanic to look over. She'll be able to spot any warning signs for that particular vehicle and tell you if that make and model is particularly unreliable, expensive to repair, etc etc.
I did not know that. I've actually just celebrated my first anniversary of owning my first car, so I am a bit of a noob. I only had one problem where a rat chewed through a fuel line, but that was only $240 with an oil change.