In my earlier posts where I talk about falling down of devotees, I once again copy another purport by Srila Prabhupada where he clearly describes the power of maya and the concept of falling down.
We may have a tendancy to find fault and an opportunity may present itself to find fault but we have to practice restraint for no one is exempt from commiting one mistake or the other. A conditioned soul makes mistakes and continues his conditioning, but if a liberated soul gets illusioned and commits mistake, then he or she is sure to fall down. Prabhupada is saying that even a liberated soul will fall down if not careful and if not under the protection of the Lord.
Therefore, it is no wonder that many devotees came to ISKCON, practiced bhakti elevated their consciousness and perhaps by the power of maya gone back to a material consciousness. As practicing devotees, we should not get disturbed and find fault or think the system is not working. Bottom line is anyone can fall victim to Maya and as a lone individual, I have to use my best judgement and care to be vigilant on all sides and pray for protection from the Lord.
Below is the purport by Srila Prabhupada
Not only does the illusory energy of the Supreme Personality of Godhead act on the conditioned soul within this material world, but sometimes it also acts on the most advanced learned scholars, who factually know the constitutional position of this material world through realization. As soon as someone thinks, "I am this material body (ahaḿ mameti [SB 5.5.8]) and everything in relationship with this material body is mine," he is in illusion (moha). This illusion caused by the material energy acts especially on the conditioned souls, but it sometimes also acts on liberated souls as well. A liberated soul is a person who has sufficient knowledge of this material world and is therefore unattached to the bodily conception of life. But because of association with the modes of material nature for a very long time, even liberated souls sometimes become captivated by the illusory energy due to inattentiveness in the transcendental position. Therefore Lord Kṛṣṇa says in Bhagavad-gītā (7.14), mām eva ye prapadyante māyām etāḿ taranti te: "Only those who surrender unto Me can overcome the influence of the material energy." Therefore no one should think of himself as a liberated person immune to the influence of māyā. Everyone should very cautiously execute devotional service by rigidly following regulative principles. Thus he will remain fixed at the lotus feet of the Lord. Otherwise, a little inattention will create havoc. We have already seen an example of this in the case of Mahārāja Bharata. Mahārāja Bharata was undoubtedly a great devotee, but because he turned his attention slightly toward a small deer, he had to suffer two more births, one as a deer and another as the brāhmaṇa Jaḍa Bharata. Afterward he was liberated and went back home, back to Godhead.
The Lord is always prepared to excuse His devotee, but if a devotee takes advantage of the Lord's leniency and purposefully commits mistakes again and again, the Lord will certainly punish him by letting him fall down into the clutches of the illusory energy. In other words, theoretical knowledge acquired by studying the Vedas is insufficient to protect one from the clutches of māyā. One must strongly adhere to the lotus feet of the Lord in devotional service. Then one's position is secure.
- SB 5.18.4