The point is that you don't decide to be born or born again. Someone else decided on that. You are correcting Jesus, not me, when you do what you do to his metaphor. To be born, you don't take action, the only action needed for you to be born, either time, was someone else's.
You misunderstand what Jesus was talking about and are stretching the analogy too far. Jesus said to Nidocemus (and he said three times).
You must be born again. As in, Nicodemus this is something you must do.
Nicodemus was puzzled. He had your attitude. He related it to physical birth.
Joh 3:4 Nicodemus saith unto him, How can a man be born when he is old? can he enter a second time into his mother's womb, and be born?
That wasn't the analogy, and that is not what Jesus had in mind. He corrected Nicodemus.
The first thing that Jesus tells him is:
Joh 3:5 Jesus answered, Verily, verily, I say unto thee, Except one be born of water and the Spirit, he cannot enter into the kingdom of God!
--He needs to born of water and the Spirit.
--Most agree that the Spirit is the Holy Spirit.
But what does the water refer to?
First, what does water do? What use does it commonly have? It is a cleansing agent. They were standing near the Temple and could probably see the ceremonial cleansings that the Jews went through before they entered the Temple.
We go back a few verses and see that the time period was the time of the Passover, and indeed Christ was in Jerusalem:
Joh 2:23 Now when he was in Jerusalem at the passover, during the feast, many believed on his name, beholding his signs which he did.
Nicodemus saw those cleansing.
His mind would wander back to such Scripture as Psalm 119:9
Psa 119:9 Wherewithal shall a young man cleanse his way? by taking heed thereto according to thy word.
--When Jesus said "water" what does water refer to? It refers to the Word of God, for it is the Word of God that cleanses as Psalm 119:9 refers to.
Later, Jesus himself would emphasize this point:
Joh 15:3 Now ye are clean through the word which I have spoken unto you.
--We are cleansed by the Word.
And then James:
Jas 1:18 Of his own will
begat he us with the word of truth, that we should be a kind of firstfruits of his creatures.
--The word "begat" has to do with "born" or born again. He brought us forth with the Word of God. It clearly connects the Word to the new birth here.
And even more clearly in 1Peter.
1Pe 1:23 Being
born again, not of corruptible seed, but of incorruptible,
by the word of God, which liveth and abideth for ever.
--Born again by the Word of God.
--Nothing could be any clearer than that.
Now back to John 3:5. There are two and only two agents by which a person can be born again. One is water (the word) and the other is the Spirit of God.
God uses the Holy Spirit as he works through His Word to bring a person to Christ. The new birth is effect through the Word of God. It is necessary to appropriate by faith. That regenerative change that happens is called the new birth or being born again. It happens at salvation or when a person is justified. This is a one-time event.
It is not such a mysterious, mystical and esoteric event as the Calvinists describe it to be.
Jesus goes on to clarify it a bit further.
Joh 3:6 That which is born of the flesh is flesh; and that which is born of the Spirit is spirit.
Joh 3:7 Marvel not that I said unto thee, Ye must be born again.
--Nicodemus you were born once, as every man is born--of the flesh.
Now you must be born a second time: of the Spirit. That takes belief or faith.
Then after a rebuke he gives him an OT illustration and application:
Joh 3:14 And as Moses lifted up the serpent in the wilderness, even so must the Son of man be lifted up:
Joh 3:15 That whosoever believeth in him should not perish, but have eternal life.
Joh 3:16 For God so loved the world, that he gave his only begotten Son, that whosoever believeth in him should not perish, but have everlasting life.
--We are saved by faith. God gave his son to be an atoning sacrifice for our sins. We must accept that sacrifice by faith. Believe on him and you will have eternal life. That is the conclusion to the new birth.