Ask HN: Disadvantages of Creating Uberjars in Clojure?

I recently just walked through the leiningen tutorial for Clojure, and I generated "Uberjars" and standard jars at the end. I was curious why the Uberjars where running by themselves, and the jars would not run and found that apparently Uberjars package all dependencies into the jar so the target machine doesn't need all of the dependencies installed separately. That seems like a lot better of a concept for distributing software, but what are the downsides besides larger files?