LOL, that is a terrible analogy. If I bought and built a boxcar and I did it wrong then yes my fault, I'm not building the phone, the manufacturer is, so as a consumer I can expect a certain level of quality.
Most consumers don't know the difference between Google-made Android phones and the others. You're missing the core point which is that the Android platform is fragmented and regular people are being given a phone full of advertising and apps built for up selling.
Regardless, the intention of my point was that manufacturers were given "blueprints" and "tools" and they built a shitty product. Even though Android is Google's product, the end result is not and to point fingers at Android is wrong. Is it the fault of Google if people are using the tools improperly? If anything, Google should've better managed the Android trademark so as to not associate their toolbox/blueprints with sub-par implementations.