Without the rupture of unexpected, there can be no experience at all.
Experience presupposes change as well as permanence. Without disruption of unexpected, there would be merely the passage of events. And a mere passage does not constitute a real change. Passage is pure continuity without interruption (a phenomenon of which humans, with the possible exception of a few mystics, have precious little experience). Change arises with a departure from continuity. Change does not, however, involve the total obliteration of continuity — there must be a "persisting non-passing content" against which an emergent event is experienced as a change.