This was supposed to be the year driverless cars went mainstream
Tech companies once promised that fully functional, self-driving cars would be on the road by 2020 and on the path to remaking transportation and transforming the economy.
But a decade after Google unveiled an autonomous car prototype with global fanfare, the technology is still far from ready, and many investors are wary of dumping more money into it — just when the world could benefit from cars that ferry people and deliver packages without a human driver.