It's a marketing truism that Americans love instant-everything except, it seems, Maxwell's ready-to-drink coffee, introduced in 1990. Problem one: manufacturer General Foods plopped the appealing 48-oz. cartons complete with an image of a mug of steaming hot coffee into supermarket coolers right next to jugs of ice-cold milk, prompting a certain amount of cognitive disconnect. Problem two: promotional materials promised the drink would be a "convenient new way to enjoy the rich taste of Maxwell House Coffee." New? Yes. Convenient? Not so much. The ready-to-drink java couldn't be microwaved in its container, and consumers, it turned out, seemed just as happy pouring from coffee pot to mug as they were from a cold carton.