The temptation to overlook the finitude of the primordial and authentic future and therefore the finitude of temporality, or alternatively, to hold 'a priori' that such finitude is impossible, arises from the way in which the ordinary understanding of time is constantly thrusting itself to the fore.
Heidegger argues that authentic temporality is constitutively finite, and that the ordinary understanding of time as endless perpetually obscures this primordial structure.
, Being and Time, 1962thesis