Added some more documentation to the release documentation.
diff --git a/src/site/asciidoc/developers/release.adoc b/src/site/asciidoc/developers/release.adoc
index fe02415..af57f42 100644
--- a/src/site/asciidoc/developers/release.adoc
+++ b/src/site/asciidoc/developers/release.adoc
@@ -157,6 +157,8 @@
=== Preparing a release
+As especially when switching a lot between different branches, it is recommended to do a clean checkout of the repository.
+Otherwise a lot of directories can be left over, which would be included in the source-release zip.
In order to prepare a release-candidate, the first step is switching to the corresponding release-branch.
After that, the following command will to all preparation steps for the release:
