I'm not sure it has to be all or nothing in terms of volume - you can have a volume model(s) yet differentiate on others. Macan accounts for nearly 50% of Porsche's volume - that's their commodity car.
For BMW, what's their volume car today? I think it's nearly all of them. I just don't know how you can produce a great product when you're spread thin across so many of them (financially and human capital wise). It's like being the GE of cars - decent stuff all around but forgettable in every one. Can survive like that but won't get fanfare in the forums
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