From Rolling Stone:
After eight flop singles, the Supremes had earned the nickname “No-Hit Supremes.” The Marvelettes — the top girl group at Motown at that point — had already passed on this song, and the Supremes didn’t like how their own recording turned out. Until it hit Number One, that is. As for that great foot-stomping beat, it’s actually two boards banged together.
Since the lead vocal was originally written to be sung by the Marvelettes’ lead singer Gladys Horton, it was arranged in a register lower than the Supremes’ lead singer Diana Ross‘ natural register. The resulting vocal track had a sensual appeal not present in Ross’ earlier songs…