You can blame the Audi A5 for the BMW 4 Series. Once upon a time, a BMW 3 Series saloon would arrive and then, a short time after, so would the 3 Series Touring, followed by a 3 Series coupé and, eventually, a 3 Series convertible.
But the Audi A5 coupé, which brought with it significant differentiation from the A4 saloon on which it was based, has changed the dynamic of the market, and has continued to with a second generation Audi A5 and the alluring Mercedes-Benz C-Class Coupé and Convertible all vying for the same buyers.
You might argue that a 3 Series is classy enough for BMW to continue with a coupé that looks and feels just like it, except with two fewer doors. But things have inevitably changed with the inexorable rise of Audi.
This, then, is the BMW 4 Series, and it’s no longer simply a slightly less practical and more desirable variant of the saloon, at least according to its maker. Instead, the two-door 3 Series has been rebranded as a model in its own right, with its own dynamic and aesthetic appeal.