How to generate javadoc jar only during deploy?

[David Hoffer]

My project currently creates javadocs during the install goal, see pom
below.  How can I configure this to run only if deploy goal is run instead?

Alternatively, is there a way this can be externalized so that individual
developers can turn this feature off when they do an install?

<plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-javadoc-plugin</artifactId>
                <version>2.5</version>
                <executions>
                    <execution>
                        <id>attach-javadocs</id>
                        <goals>
                            <goal>jar</goal>
                        </goals>
                    </execution>
                </executions>
</plugin>