Language Packs (LP) are different than regular Windows Updates. Once approved in WSUS, they only install through manual intervention on the client. If the language pack is NOT approved, you will still be able to add the language pack for writing in the chosen language, but the display will stay to the currently loaded interface pack (English). If you wanted to load the Language Interface Pack (LIP), you have to go to Language Settings > Select the Language > Click on “Download and install language pack”. The updates are then installed and when reported back to WSUS, they will be removed them from the ‘needed’ updates. This will get it from the WSUS Server and load the language interface pack into Windows.
With language packs and language interface packs, the updates work more along the lines of PRESENTING the user with the updates, rather than forcefully installing them.