McDonald's has become part of the cultural landscape in ways no other fast-food joint has managed, and is in some ways responsible for the invention of the entire modern concept of fast food. Despite all their success, McDonald’s has experienced some failures in their attempt to create innovative products, like this burger that was discontinued back in 1991.

In 1991, McDonald’s discontinued their McDLT, a burger with lettuce, tomato, and mayonnaise that was intended to be a half-cold, half-hot burger. The hot and cold ingredients for the burger came packaged separately, which required customers to assemble it themselves, and it even had a slogan: "Keep the hot side hot, and the cool side cool."

There are several possibilities as to why the McDLT failed, such as the fact that it required polystyrene packaging for insulation at a time when McDonald’s was trying to be more environmentally-friendly. It also could have had something to do with most locations using normal heating racks, but the simplest (and best) explanation is that a half-cold burger is just too weird.