For something to "fail" in the Bible means there is not enough understanding of truth and desire for good for someone to attain a higher spiritual state -- and possibly not enough to overcome false thoughts and the desire for evil at all. "Abate" has similar meaning but in an opposite sense, usually referring to the lessening of evil and falsity at the end of a state of temptation.

In Genesis 8:3, Deuteronomy 34:7, Judges 8:3, and Leviticus 27:18, the abating of the flood waters signifies the cessation of temptations. (Arcana Coelestia 843, 849)

(Referenser: Arcana Coelestia 857, 5969, 6122, 8395)

849. 'The waters abated at the end of a hundred and fifty days' means that temptations came to an end. This clearly follows from what has been said above. That 'a hundred and fifty days' means the finishing point is clear from what has been stated concerning the same number at Chapter 7:24. So here that same number means the point at which fluctuation ends and new life starts.