"Says who ?" That is just my interpretation but the following passages are interesting.
"Monks, there is a not-born, a not-become, a not-made, a not-compounded. Monks, if that not-born ... were not, there would be no escape here from what is born, become, made, compounded. But since, monks, there is a not-born ... therefore there is an escape from what is born, become, made, compounded". Itiv. 43. Translated by Nanananda, Concept and Reality, pages 71-72.
"By knowing the destruction of formations be thou O Brahmin, one who knows the unmade" Dhp. 383.
"And it is hard to see this truth, namely, the stilling of all formations, the relinquishing of all acquisitions, the destruction of craving, dispassion, cessation, nibbana". MN 26. 19.
"There is, monks, that sphere wherein there is neither earth nor water nor fire nor air, wherein is neither the sphere of infinite space, nor that of infinite consciousness, nor that of nothingness, nor that of neither-perception nor non-perception; wherein there is neither this world nor a world beyond, nor moon and sun. There, monks, I declare, is no coming, no going, no stopping, no passing away, no arising. It is not established, it continues not, it has no object. This, indeed, is the end of suffering." Ud. 80. ( Nanananda page 71 ).
"That end of the world wherein one is not born, does not grow old or die, pass away or reappear, that I declare, is impossible to be known, seen or reached by travelling. But, friend, I do not declare that one can make an end of suffering without reaching the end of the world. Friend, I do proclaim that in this very fathom-long body, with its perceptions and consciousness, is the world, the world's arising, the world's cessation and the path leading to the world's cessation. A.N. II. 48
Best wishes, Vincent.