Krishna repeats the point with added force. The same host of beings comes into existence again and again, and dissolves again and again. When Brahma's night arrives, they vanish — helplessly. When his day dawns, they reappear.
"Avashah" — helplessly — is a powerful word. These beings have no say in the matter. They are born and they perish according to the rhythm of nature. Waves rise and fall in the ocean — not because they choose to, but because that is the ocean's nature.
Hearing this stirs a natural sense of detachment. If this world is created and destroyed over and over, what is the point of clinging to it? Far wiser to seek refuge in the eternal Lord who stands beyond this cycle altogether.