Being deep and appearing deep.— Whoever knows he is deep, strives for clarity; whoever would like to appear deep to the crowd, strives for obscurity. For the crowd considers anything deep if only it cannot see to the bottom: the crowd is so timid and afraid of going into the water.Maybe it's just a targeted clarity.
Nietzsche (GS §173)
On the question of being understandable.— One does not only wish to be understood when one writes; one wishes just as surely not to be understood. It is not by any means necessarily an objection to a book when anyone finds it impossible to understand: perhaps that was part of the author's intention—he did not want to be understood by just "anybody". Every more noble spirit and taste selects its audience when it wishes to communicate itself; and choosing them, one at the same time erects barriers against "the others". All the more subtle laws of any style have their origin at this point: they at the same time keep away, create a distance, forbid "entrance," understanding, as said above—while they open the ears of those whose ears are related to ours.
Nietzsche (GS §381)