And two why its not. Its got four doors and only six cylinders….
BMW introduced its legendary M3 in 1986. The $64,000 four-door basically created the then-novel “sport sedan” segment. In the years since, it has maintained its dominance with supreme handling, punch-perfect power, and businesslike good looks—and has rightfully been embraced by wealthy professionals as the best drivers’ sedan you can get for the money.
Last year BMW sold roughly 63,000 “M” vehicles total, a record-setting increase of 40 percent over 2014. The M3/M4 models, which are traditionally counted together, represent the majority of that number, says BMW.
More here – Bloomberg
PS: If I were looking at this segment again this would be the car I would buy – Mercedes-AMG C 63 S Coupe 2016