When building a Maven artifact of type ear, the ear packaging type is invoked.
The maven-ear-plugin replaces the maven-jar-plugin at this point, so it is as though you included it in your pom.xml.
The generate-application-xml goal binds by default to the generate-resources phase.
The ear goal binds by default to the package phase.
So at the end of the day by declaring a packaging type of ear, you cause two goals—not one—to be run.
Blame Laird 