First, I agree with John, The Book of Judges is the best example of those who fail away.
This is because Signs, Miracles, Sign Gifts or even spiritual gifts will not save man. Gifts only gives validity to the source (confirms authority), thus sign gifts were given to many during the apostolic years of the New Church, such was use to confirm their word.
Mark 16:17-20. And these signs shall follow them that believe; In my name shall they cast out devils; they shall speak with new tongues; They shall take up serpents; and if they drink any deadly thing, it shall not hurt them; they shall lay hands on the sick, and they shall recover. So then after the Lord had spoken unto them, he was received up into heaven, and sat on the right hand of God. And they went forth, and preached every where, the Lord working with them, and confirming the word with signs following. Amen.
Thus, we have the complete word of God, which is greater than signs, even miracles.
2 Peter 1:18-19. And this voice which came from heaven we heard, when we were with him in the holy mount. We have also a more sure word of prophecy; whereunto ye do well that ye take heed, as unto a light that shineth in a dark place, until the day dawn, and the day star arise in your hearts:
Jesus also confirmed that miracles wouldn't save man, only his word. Salvation is a heart change, done only through faith, not miracles.
Matthew 12:38-39. Then certain of the scribes and of the Pharisees answered, saying, Master, we would see a sign from thee. But he answered and said unto them, An evil and adulterous generation seeketh after a sign; and there shall no sign be given to it, but the sign of the prophet Jonas:
Luke 16:31. And he said unto him, If they hear not Moses and the prophets (God's Word), neither will they be persuaded, though one rose from the dead (A Miracle).{read in context Luke 16:20-31}
If God rain extraordinary miracles today, it would cause man pause temporarily, but in and of itself, miracles will not change the heart of man. It will only cause man to seek more miracles, more signs.
Good Day and God Bless