Strong faith or no faith are the two greatest determinants for leaving the Soka Gakkai.

Question: Is it easy or difficult to leave the Soka Gakkai?
Answer: That depends: General member, leader, amount of time in the organization; correct, incorrect, or no faith in the Lotus Sutra, the Gohonzon, the doctrines of Soka Gakkai, the doctrines of Nichiren, etc; strong or weak SGI practice; friends in and out of the organization; relationship with leaders; mood; state of mind; family in or out of the organization; interests outside of the organization; studied or not; obstacles or perceived punishment; value placed on honesty; hopes and desires...

On this last point. Suppose you desire a copy of a Nichiren inscribed Gohonzon. if your desire was strong, you have absolutely no choice but to leave the organization since copies of Nichiren inscribed Gohonzons are verboten. Depending on the strength of your desire [to practice as the Daishonin taught] it can be easy or difficult to leave the organization. Where there is no faith in the Lotus Sutra, it is easy to leave. Where there is strong faith but little study, it can be very difficult [because one has been brainwashed and propagandized to believe that only the Soka Gakkai upholds the Lotus Sutra]. 

Faith in the doctrines of the Soka Gakkai was simultaneously one of my biggest impediments to an easy transition and the source of my determination to leave the Soka Gakkai. Let me explain. Having been indoctrinated that Soka Gakkai activities was the source of both Enlightenment and the only way to realize the widespread propagation of the Lotus Sutra [Kosen Rufu], for years, I threw myself into activities at the expense of my profession, my family, my personal development etc yet it was still very difficult to determine to leave because my Great Wish was stronger than my "smaller wishes". On the other hand, my unrealizable "small wishes" [because of the time allotted to SGI activities] made it very easy to decide to leave, especially after studying deeply the writings of Nichiren Daishonin and comparing them to the SGI teachings.

If one is "happy", it is extremely difficult to leave the SGI despite the inconsistencies of their doctrines and their failure to act as they speak. Who cares if Nichiren and the Lotus Sutra teach that Shakyamuni is the Original Eternal Buddha, there is no proof that Nichiren inscribed the DaiGohonzon, that there is no place for interfaith practice, or the fact that a living master in the seat of Law is not a cardinal doctrine, let alone THE cardinal doctrine of the Lotus Sutra?  "I'm happy." It may take a great faith in the teachings in the face of the winds of pleasure, prosperity, praise, and honor to leave the SGI. 

Strong faith in the teachings and in Nichiren or no faith whatsoever, are the two greatest determinants for leaving the Soka Gakkai.