Because you can't let one ugly model intrude on the sales of another.
It hasn't even officially launched yet and already BMW is claiming that the upcoming X4 won't be given the M division treatment. Set to face off directly against the likes of the Range Rover Evoque and Audi Q3, the X4, or at least the concept version, pretty much looks like a smaller version of the X6, albeit with some updated doses of BMW's current styling language. So why won't there be an X4M? The simple answer is because of the X6M.
According to a new report from CarAdvice, a BMW manager stated that (in reference to a potential X4M) "It is a little bit selfish, as it is not always about what a number of customers would like but what for us is the best business opportunity." Basically what BMW is saying is that an X4M would put a dent in sales of the more expensive X6M; it'd be bad business to be competing against yourself. The X6M is currently enjoying strong sales, and considering it starts at nearly $93,000, it's not at all hard to understand BMW's logic here. If at a later date BMW realizes that an X4M would be profitable after all, we wouldn't put it past them to quickly give it the production green light.