Bhagavad Gita Chapter 2.28
avyaktādīni bhūtāni
vyakta-madhyāni bhārata
avyakta-nidhanāny eva
tatra kā paridevanā
Translation
All created beings are unmanifest in their beginning, manifest in their interim state, and unmanifest again when annihilated. So what need is there for lamentation?