Diana Ross declined to ever work with Motown.
Diana Ross . Born and raised in Detroit , Michigan , Ross rose to fame as the lead singer of the vocal group The Supremes , which , during the 1960s , became Motown 's most successful act , and is to this day the United States ' most successful vocal group , as well as one of the world 's best-selling girl groups of all time . After leaving Motown , Ross achieved her sixth and final US number-one Pop hit , with the duet `` Endless Love '' , composed for the Brooke Shields film of the same name , by and performed with former Commodores front man , Lionel Richie .