The line comes from the 2004 comedy Anchorman: The Legend of Ron Burgundy, starring Will Ferrell as the pompous 1970s newsman Ron Burgundy. After losing his job and wandering the streets dishevelled, he drinks milk on a blisteringly hot day and immediately regrets it. The scene became one of the film's most quoted moments, spreading through quote pages, GIFs and reaction videos. It endures because the regret is universal, used whenever food, drink or any poor plan backfires in public online.