Self-fulfilling prophecy much? When all the comparisons go like "Can these other brands meet or beat the standards we think BMW has set?" then the comparison is not a Car1 v. Car2 v. Car3 v. Car4. The comparison becomes "How much like Car1 are Car2, Car3, and Car4?"
All the brands are trying to be anointed King by the press. BMW is not a best seller because it's the "best" car. It's a best seller because people have been told it's the best car by the press for the past 20 years. The CTS, 3-series, 5-series, TL, IS, A4, C-Class, G35 all perform close enough that most of the differences come down to things only noticed on the track. The real differences are things like interior design and quality, fuel efficiency, room and utility, and over all fit and finish. The 3-Series may have the smoothest engine, but the interior is majorly outclassed by the CTS and A4. It's out done in terms of comfort by the TL and IS. The CTS, G35, and A4 all pull corners with Gs that meet or exceed the 3-series. The CTS is also one of the safest of the bunch. I'd also pick the CTS <from my own experience> and TL over the BMW in terms of reliability. Suzy McMansion wants a BMW because her husband read the latest BMWTrend and because it will annoy Tammy Trailerpark at work.
So... No, it isn't clear that BMW is the ultimate driving machine..... however it's the ultimate PR machine.