This place is used for cleaning the discussion forum. Even old discussions can be activated after long periods, but to finding them will be easier if old advertising / spam / etc is removed from that board. For informational reasons, topics won't be simply deleted, but moved here. Out from sight, but still available for reading if necessary.
Not all ads/news are removed. Some which include reviews/comments or potentially continue with further label news will remain on main discussion board. Cleaning is not systematic, so it will happen once in a while, when it seems that news/ad has received the full attention.