there is a large amount of reasons for a tight hole status.
imagine the namibian governement is negociating futur blocks right close from this area and the final result is a dry hole and is annonced 2 days before a contract signature ...it could be enough to lose some rentals revenues
you can also figure that whit a hit those government want the glamour of the annonce .
there is 100 s of reason for a tight hole status