Why, because Toyota people say so? I've had way better reliability from my American vehicles than my Japanese one. (All Honda, and no Toyotas though) My boss bought a brand new, first year GEN2 Tundra, and had to replace 3 wheel bearings in the first year. When I asked if it was all the same wheel bearing, just improper installation, the answer was, "no it was the bearings on 2 different wheels." Kind of an odd issue to have with a brand new, 2WD 1/2 ton. I've known 2 people with Lexus ES300's whose engine needed replacing, and one was at roughly 120K, and the other around 150K if I remember right.
Do I feel that Toyota vehicles are generally reliable? Yes, but they can and do have issues too. My in-laws bought a new Camry to replace their 07 Camry 2-3 years ago. They kept having to spend for repairs. The one I remember was they needed a new exhaust manifold because the cat clogged on their I4 car. Now you might say, "but the car had 300K miles." Cool, but going 300K, on a properly maintained vehicle isn't unheard of, or some special feat. I've known people pushing noticeably more mileage than that, and not having to constantly repair their vehicles. I know a guy who had an 89 Mustang LX with 400K on the factory drivetrain. I've known a couple pre-AFM 5.3L Silverado owners with around 400K miles. Are there Toyota's with that kind of miles that needed little $ spent in repairs and upkeep? Sure, but the point is Toyota generally being reliable doesn't mean that other vehicles aren't reliable in general either. This is why I say reliability is overrated. I don't want a vehicle with that much wear and tear on it. At that point I'd rather get something fresh and modern.