Doing a Maven build can sometimes take a couple of minutes during which you will probably do something else. It might happen that the build fails within a couple of seconds, but since you expect it to run for a couple of minutes you will only look at the command prompt after a while.
Recently a Maven desktop notifier has been released for Mac OS X, Linux and Windows.
With the desktop notifier you will get instant feedback while performing Maven builds. It even differentiates between successful and failed builds. The project is open source and can be found on Github.