In ISKCON, especially in the past and also in the present, I have read, and seen how devotees show obedience only to "pure devotees" and not so much to other devotees. I think this very reason is why there are many factions. After Srila Prabhupada left the planet some disciples of his started to question the authority of the then leaders and still question now. They think no one is a pure devotee as pure as Srila Prabhupada. Citing that as an excuse, many devotees left ISKCON either looking elsewhere for devotees or just plain left spiritual life altogether.
Some created their own groups criticizing the gurus of ISKCON and slandering their character. I admit, although, there were genuine misgivings, still the general aura is that beyond Srila Prabhupada there is no one who can be seen as pure and hence display an air of disobedience towards them. Srila Prabhupada may have been a saktyavesa avatar and nitya siddha, but because the other Gurus or leaders of ISKCON are not like Prabhupada I will not be obedient to them is not the proper mood of a devotee. This sort of mentality is the reason we have many groups and factions within and without ISKCON. This is not what Srila Prabhupada wanted.
To prove that this sort of mentality comparing current gurus to Srila Prabhupada and that they are not pure enough and hence will not be obedient to them is wrong. Below is a letter by Srila Prabhupada himself on this specific matter.
But I think you have got the mistaken idea in this connection. You speak of pure devotee, that he is saktyavesa avatara, that we should obey him only--these things are the wrong idea. If anyone thinks like that, that a pure devotee should be obeyed and no one else, that means he is a nonsense.
We advise everyone to address one another as Prabhu. Prabhu means master, so how the master should be disobeyed? Others, they are also pure devotees. All of my disciples are pure devotees. Anyone sincerely serving the spiritual master is a pure devotee, it may be Siddhasvarupa or others, a-Siddhasvarupa. This must be very clearly stated. It is not only that your Siddhasvarupa is a pure devotee and not others. Do not try to make a faction. Siddhasvarupa is a good soul. But others should not be misled. Anyone who is surrendered to the spiritual master is a pure devotee, it doesn't matter if Siddhasvarupa or non-Siddhasvarupa. Amongst ourselves one should respect others as Prabhu, master, one another. As soon as we distinguish here is a pure devotee, here is a non-pure devotee, that means I am a nonsense.
Why you only want to be in the spiritual sky with Siddhasvarupa? Why not all? If Siddhasvarupa can go, why not everyone? Siddhasvarupa will go, you will go, Syamasundara. will go, all others will go. We will have another ISKCON there.
-Srila Prabhupada letter to Tusta Krishna 14 Dec 1972
Clearly, Srila Prabhupada is making a case that to think to submit to only pure devotee and not to other senior devotees is a fallible idea and as Prabhupada says "nonsense" on our part. Yes, the current gurus may not be nitya-siddha devotees and may be still conditioned, but still if they sincerely follow the instructions of their spiritual master without deviations, they can be considered liberated and worth surrendering towards. That is why Prabhupada categorically says everyone is a pure devotee and that everyone will go to the spiritual sky. The definition of pure devotee according to Srila Prabhupada is not an esoteric concept but simply based on one fundamental point and that is if a devotee is fully surrendered to the instructions of his guru, then he is a pure devotee and to such a pure devotee, we can surrender. No where in the letter Prabhupada defines pure devotee based on nitya siddha or other esoteric qualifications.
I am writing this post because I read this letter and reflected on how so many new devotees are bewildered by other factions and the reasons they give to accept only Prabhupada as guru and how they find fault with all the existing gurus. At one point, I was one of the devotees bewildered by the bickering and fault finding between devotees. I think this letter by Prabhupada clearly addresses this issue.