Srila Prabhupada - "Free will means that you can act wrongly, that is free will. Unless there is chance of doing wrong or right, there is no question of free will." (Discussions Prabhupada - Rene Descartes)

Having "free will" is the constitutional make up of all marginal living entities (jiva-souls) that is ALWAYS part and parcel of their eternal identity and personality in the spiritual world.

This means the jiva-souls can even choose to leave the Vaikuntha planets or Goloka-Vrindavana if they choose, this is also what free will allows and if it didn't, then the jiva-souls have no free will.

This is why it is foolish that big, big sannyasis, gurus and Vaisnava scholars who claim once entering the spiritual world, the jiva-souls can never fall down again to the material world.

No, they CAN fall down again and again if they choose to do so! 

And such fall downs have nothing to do with Maya (material energy) because there is no Maya in the spiritual world, but there is ALWAYS free will. Maya or material energy does NOT exist in Vaikuntha or Goloka-Vrindavana.

The choice to leave Vaikuntha or Goloka-Vrindavana is possible because Krsna allows voluntary loving exchanges which is only possible in a "two-sided" relationship, this also allows one to accept or reject Krsna if they choose.

Srila Prabhupada  - "Free will means that you can act wrongly. That is free will. Unless there is chance of doing wrong or right, there is no question of free will. Where is free will then? If I act only one sided, that means I have no free will. Because we act sometimes wrongly, that means free will."

Hayagriva - "A man may know better but still act wrongly."

Srila Prabhupada - "Yes, but that is free will. He misuses his. Just like a thief, he knows that his stealing, it is bad, but still he does it. That is free will. He cannot check his greediness, so in spite of his knowing that he is doing wrong thing—he will be punished, he knows; he has seen another thief, he was punished, he was put into prison— everything he knows, but still he steals. Why? Misuse of free will. Unless there is misuse of free will, there is no question of free will." (Excerpt from: Philosophy Discussions with Srila Prabhupada – Rene Descartes)

Srila Prabhupada – "So everyone can know that independence means one can use it properly, or one can misuse it. That is independence. If you make it one way only, that is not independence, that is force." (Los Angeles, June 23, 1975)

Srila Prabhupada – "You have got little independence therefore you can violate. Because you are part and parcel of God you have got independence, proportionately, therefore if he likes he can return. That independence has to be accepted, little independence. We CAN misuse that." (Conversation, Mayapur, Feb 19, 1976)

Syamasundara - "But can we predict returning back home back to Godhead will be permanent? Can we predict that? Just like many prisoners leave the prison, however some do come back?"

Srila Prabhupada - "No, there is no permanent effect because we have got little independence. There is nothing permanent because you can misuse your independence at any time."

Syamasundara - "And some come back?"

Srila Prabhupada - "Yes, otherwise there is no meaning of independence. Independence means you can do this, you can do that. "All right. Whatever you like."

Devotee - "Then he is so many times falling down, again and again, so will he eventually permanently come back?"

Srila Prabhupada - "He has got independence, therefore there is always the possibility he can misuse his independence, he CAN fall down. That's why when a man is released from the prison house, that does not mean permanently because he can come back again, the general law is NOT to come back, but if he likes, he can come back, otherwise what is the meaning of independence? Just like one becomes free from the prison house, naturally he should not go there again." (Discussions with Syamasundara - Henri Bergson)

Even though Krsna has promised there is no return to the material creation once returning to the spiritual world, there IS return if the jiva-souls want to return to the material world as Prabhupada explains here-

Acyutananda – "In Bhagavad Gita Krsna says, once coming to the spiritual world, the jiva-soul never returns to the material world, so He can return?"

Srila Prabhupada – "If he likes he can return."

Guru-kripa – "How is it that one can become envious of Krsna?"

Srila Prabhupada – "You have got little independence, you can violate. Because you are part and parcel of God. God has got full independence, but you have got independence too, proportionately, because you are part and parcel, so if he likes, he can return. That independence has to be accepted. We can misuse that. Krsna-bahirmukha haïä bhoga väïchä kare. That misuse is the cause of our falldown." (Conversation, Mayapur, Feb 19, 1976)

Devotee - "Well, I believe you once said that once a conditioned soul becomes perfected and gets out of the material world and he goes to Krsnaloka, there’s no possibility of falling back."

Srila Prabhupada - "No! There is possibility, but he does not come IF he is intelligent. Just like after putting your hand in the fire, you never put it in again. So those who are going back to Godhead, they MUST become intelligent. Why going back to Godhead?" (Prabhupada discussion with Syamasundara Dasa)

Srila Prabhupada - "As soon as we try, "Oh, this material world is very nice, yes, Kṛṣṇa says, yes, you can go. Otherwise what is the meaning of free will? Every living entity has got a little free will. And Kṛṣṇa is so kind, He gives him opportunity, "All right, you enjoy like this." It is free will." (Morning Walk At Cheviot Hills Golf Course, May 13, 1973, Los Angeles)

Srila Prabhupada - "So everyone can know that independence means one can use it properly or one can misuse it. That is independence. If you make it one way only, that you cannot fall down, that is not independence, that is force. Therefore Krsna says, yathecchasi tathä kuru. “Now you do whatever you like." (Los Angeles, June 23, 1975)

Therefore, returning back home back to Godhead is NOT necessarily permanent Prabhupada has explained above, that choice to stay, or go ALSO is the jiva-soul's choice too.

It is NOT just a "one-sided decision" that only Krsna makes, no, real loving exchanges can NEVER exist in such a "one-sided" relationship because there is ALWAYS "free will" in the spiritual world that also allows the jiva-souls to choose for themselves what they want to d,  even if that means rejecting Krsna.

This is what is really going on in the spiritual world's of the Vaikuntha planets and Goloka-Vrindavana.  

Srila Prabhupada - "If you have no free will, then you are a stone. The stone has no free will. You want to be stone? Then you must have free will. But don't misuse your free will. But don't try to become stone either. That is not life". (August 5, 1976, New Mayapur France)^