Zen is not for Everyone

A special transmission outside the scriptures;
Not dependent upon words or letters;
Direct pointing to the mind;
Seeing into one's Nature and recognizing buddhahood.

Zen attempts to enlighten through practice. Enlightenment is a state in which the individual is freed from individuality, from preconceptions, from conceptions, from judgments, from truth. The enlightened person knows what is involved in taking up an interpretation of reality in order to survive and communicate. The enlightened person is free from the suffering caused by desire. The enlightened person helps others towards enlightenment as easily as breathing, since the barrier between self and other has been knocked down. From wisdom springs deepest compassion.

Zen is simple -- just sit and work on discarding your frame of reference! A teacher can help you by guiding your practice from outside and helping you come to realizations.

Zen does not claim to be the only route to enlightenment, and not everyone can get there through Zen practice. It requires openness and self-examination that does not come naturally to everyone. Some claim it requires a higher than average intelligence (I'm not convinced). In any case the direct, non-linguistic transmission won't work for many people who lack the necessary faculties for whatever reason. Other ways are available to them, some of which are probably not accessible to some Zen practitioners.

The urge to convert other people to your own way of thinking is based in a feeling of insecurity. You need the approval of other people to support your own thought, so you try to "recruit" them to your way of thinking. They can then support your ego. This is ultimately counter-productive, because a strong ego results in cognitive dissonance -- the inability to accept reality -- and this is a barrier to enlightenment.

Work on yourself, and help others to work on themselves, but do it by example, and by giving them the benefit of your insights without requiring their acceptance in return. Do not presume that your way is the best way, just because it might be the best way for you. Pretty soon you'll realize that the whole idea of a "best" way is bogus.