why does site-deploy rebuild so often?

[David Hoffer]

We keep having problems with our site-deploy build either hanging or running
out of memory.  I just noticed that it rebuilds everything about 11 times!
Why?

(This top level pom has 3 modules where those 3 modules each have a few
modules.  This is the only pom with a reporting section.)

Here is our top level reporting section.

<reporting>
        <plugins>
            <plugin>
                <groupId>org.codehaus.mojo</groupId>
                <artifactId>javancss-maven-plugin</artifactId>
                <version>2.0-beta-2</version>
            </plugin>
            <plugin>
                <groupId>org.codehaus.mojo</groupId>
                <artifactId>cobertura-maven-plugin</artifactId>
                <version>${cobertura-maven-plugin.version}</version>
            </plugin>
            <plugin>
                <groupId>org.codehaus.mojo</groupId>
                <artifactId>surefire-report-maven-plugin</artifactId>
                <version>2.0-beta-1</version>
            </plugin>
            <plugin>
                <!--Provides creating jar of source-->
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-source-plugin</artifactId>
                <version>${maven-source-plugin.version}</version>
            </plugin>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-javadoc-plugin</artifactId>
                <version>${maven-javadoc-plugin.version}</version>
                <configuration>
                    <aggregate>true</aggregate>
                </configuration>
            </plugin>
            <plugin>
                <groupId>org.codehaus.mojo</groupId>
                <artifactId>jxr-maven-plugin</artifactId>
                <version>2.0-beta-1</version>
            </plugin>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-pmd-plugin</artifactId>
                <version>2.4</version>
                <configuration>
                    <targetjdk>${jdkVersion}</targetjdk>
                    <rulesets>
                        <ruleset>/rulesets/basic.xml</ruleset>
                    </rulesets>
                    <format>xml</format>
                    <linkXref>true</linkXref>
                    <sourceEncoding>utf-8</sourceEncoding>
                    <minimumTokens>100</minimumTokens>
                </configuration>
            </plugin>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-project-info-reports-plugin</artifactId>
                <version>2.1.1</version>
                <reportSets>
                    <reportSet>
                        <reports>
                            <report>dependencies</report>
                            <report>dependency-convergence</report>
                            <report>project-team</report>
                            <report>cim</report>
                            <report>license</report>
                            <report>scm</report>
                            <report>index</report>
                            <report>summary</report>
                        </reports>
                    </reportSet>
                </reportSets>
            </plugin>
        </plugins>
    </reporting>