If you configure "Subversion Tagging" as action "After successful release build" the build is not tagged.

Console output is:
Building on master in workspace /data/jenkins/jobs/SVN-Jenkins-Test/workspace
Updating
http://svn.local/svn/jenkins_test/trunk
at revision '2017-04-04T18:27:56.228 +0200'
At revision 3

No changes for
http://svn.local/svn/jenkins_test/trunk
since the previous build
Starting to tag
No Subversion tagging for unsuccessful build.
Finished: SUCCESS
If same configuration is used as post build action for the normal build, the repository is tagged correctly.