Swing/AWT Visually

Why do all applications produced using Swing/AWT tend to look alike, and clunky?
Could someone have come up with a better design/visual feel than monotone gray/boxy?

Or am I just seeing the worst of the pack? Specifically, today I'm looking at the Oracle Enterprise Manager Console. Just seems that a ton of Java apps look unprofessional due to the clunky feel of the defaults...