diff --git a/core/src/main/java/hudson/maven/MavenModuleSetBuild.java b/core/src/main/java/hudson/maven/MavenModuleSetBuild.java
index 282862f9c0bbc77a70c8a08fa5853fd1ce4893d7..bbd9244fd75217846d53bd44b4347b70e5d7ac37 100644
--- a/core/src/main/java/hudson/maven/MavenModuleSetBuild.java
+++ b/core/src/main/java/hudson/maven/MavenModuleSetBuild.java
@@ -364,6 +364,9 @@ public final class MavenModuleSetBuild extends AbstractBuild<MavenModuleSet,Mave
 
     /**
      * Runs Maven and builds the project.
+     *
+     * This is only used for
+     * {@link MavenModuleSet#isAggregatorStyleBuild() the aggregator style build}.
      */
     private static final class Builder extends MavenBuilder {
         private final Map<ModuleName,? extends MavenBuildProxy2> proxies;