Reports that the relationship was rocky surfaced on and off last year, although Hyundai's Joel Ewanick, VP-marketing, continually denied there was any client-agency friction.
Hyundai dealers were unhappy with Goodby's cerebral "Think About It" campaign, the executives said. Also, Hyundai's president-CEO, Jong Eun Kim, who arrived in January, was losing patience that the agency's work for the $80 million launch of the new upmarket Genesis sports sedan wasn't working, one of the executives said.
Hyundai introduced the Genesis to the U.S. market during this year's Super Bowl even though the car, with a base price of $33,000, wasn't arriving in showrooms until June.
Hyundai has only sold a little more than 1,800 of the cars through August, missing its target of more than 2,000 monthly.
Executives at Goodby were unavailable for comment.
This has been a busy year for the automaker. Earlier this year, Interpublic Group of Cos.' Initiative won Hyundai and affiliate Kia Motors America's $700 million-plus media account after a review. A year ago, it moved its $30 million U.S. Hispanic account to Omnicom Group-backed LatinWorks, four months after tapping Omnicom's Goodby, Silverstein & Partners for the national general creative account.