Brokerages one after another are lowering their price targets after the automaker failed to chart a course for its Atlas dreams.

Hyundai Motor got off to a dazzling start this year with the unveiling of an acrobatic Atlas humanoid robot developed by its U.S.-based robotics subsidiary, Boston Dynamics, in January. 

The robot stole the spotlight at CES, and Hyundai’s shares went on to soar to an intraday record of 787,000 won ($580) on June 1, up 163 percent…