The Japanese companies’ decision to call off negotiations highlights the challenges legacy automakers face in partnering to tackle new technologies.

Less than two months after a potential merger was floated, Honda and Nissan have called the potential partnership off, forcing Nissan, which has been experiencing difficulties, to explore alternate collaborations.

Although Mitsubishi considered joining the Honda-Nissan merger, that was old news by late January. That alliance might have been part of the problem. Although not an actual merger, the car companies involved each own stakes in the other—in Renault's case,