Because that would suck.
Hands down, Cadillac has one of the coolest CEOs in the industry. Johan de Nysschen is a car guy through and through and he's not happy about Google and Apple attempting to get into the car business. More specifically, autonomous driving troubles him. Wards Auto is reporting that at the recent JD Power Automotive Marketing Roundtable, de Nysschen described autonomous cars as a "nightmare" and the idea of "taking the fun out of driving by letting a robot transport us."
He's aware that driver error causes roughly 90% of accidents, but pure autonomous cars would, more or less, suck. Instead, he stated that "autonomous driving and driving passion must co-exist. We're after balance. Many autonomous car (prototypes) emphasize sheer functionality," de Nysschen said in reference to a Google car. "It would be a mind-numbing experience going from point A to B. My goodness, you might as well take the bus." What he wants Cadillac to achieve is the ideal blending of technology and driver. For example, Cadillac's new semi-autonomous Super Cruise system. "The difference between Super Cruise and fully autonomous lies more in the legal than the technical arena. I'll leave it at that."