In a computerworld article, Gosling said:
"The big problem that Swing has is that it's big and complicated. And the reason that it's big and complicated is that it is the most fully featured, flexible, whatever-way-you-want-to-measure-it UI [user interface] tool kit on the planet. You can do the most amazing things with Swing. It's sort of the 747 cockpit of UI design tool kits, and flying a 747 is a little intimidating, and what people really want is a Cessna."
Sure, the 747 still needs some work, but Sun has a fleet of planes to take care of. And they do it at virtually no cost.