Just like, in my, this life, I can experience. In each stage of my life, I have my past, present and future. You are all young boys. You had your past, as a child, as a boy. Now you are young, and your future is also there as old, as I have become old. So in any stage of life, there is past, present, and future. So why not, I am old man, so when I shall die, why there is no future? There must be future. I had my past, I am at present, and there must be future also. The future is that I must get another body. That body may be of animal or trees or demigod or God. That is stated in the Bhagavad-gītā, yānti deva-vratā devān pitṝn yānti pitṛ-vratāḥ [Bg. 9.25].
You can prepare yourself for your next body. So ultimate goal is to get a body in the kingdom of God. That is—saṁsiddhiṁ paramaṁ gataḥ—that is highest perfection. You can get a body next in, as a human being in the rich man's family, or as a king, or as a leader, or as a cat, as a dog, as a tree. That will depend on your work. Similarly you can get your next body as associates of God, Kṛṣṇa. That is stated, that you can have, mad-yājino 'pi yānti mām [Bg. 9.25]. "Those who are My devotees, they come to Me," Kṛṣṇa says.
Prabhupada's lecture - Śrīmad-Bhāgavatam 1.2.8 - New Vrindaban, September 6, 1972