Is zazen practised for its own sake, or as a means to end suffering? Experts seem to say different things It is confusing to me that what what the goal of zazen is (and is not), as proposed by various people with more or less authority on the subject, varies so greatly. Some say no goal, and others identify various goals.

Rationally speaking, no goal makes sense. It is a form of non-dualism. If there is a goal, then there is an attachment to becoming something which one is not. But no goal is also nonsense. If there is no goal, then there is no goal to end suffering. The Four Noble Truths become descriptive, and the Eightfold Path is unimportant.

This is as far as my thinking has gotten. I conclude with some verifiable examples of what the goal of zazen is said to be.

remove wrong perceptions


  the practice of meditation, the practice of looking deeply, has the purpose of removing wrong perceptions from us
  —“What is Nirvana and How Does It End Suffering?” by Thích Nhất Hạnh at MeditationPlex


see ourselves


  Zazen deliberately tries to remove all entertainment and distractions from our minds so we can see ourselves as we really are
  —The Laughing Teabowl Sangha


there is no goal


  There is no starting point nor goal, nothing to attain
  –Zen Mind, Beginner’s Mind by Shunryu Suzuki


grasp enlightenment


  the only way to grasp enlightenment is through a calm and settled mind
  —Zen Guide


engage with reality (not to make your life better)


  The real practice of Zen is to engage directly with reality, not to use it as a method to improve your health or make your life better
  —“Zazen Posture” by Josho Pat Phelan at Chapel Hill Zen Center


not to learn


  Don’t think of practice in terms of “eventually”
  —“Zazen is not step-by-step learning meditation” by Harada Sekkei Roshi at Buddhism Now


compassion


  the purpose of zazen is compassion
  —“Beyond Thinking: Dogen’s Teachings on Zazen” by Norman Fischer at Upaya Zen Center
Actually, the answer is very simple: meditation is practiced to achieve tathata (suchness), which is a state of realization of the Third Noble Truth. Because tathata involves cessation of aversion to any "this" and of longing for any "that", its attainment requires a mindset without a goal. It would be more precise to say that no-goal is a method of meditation, but that would risk leaving some subtle shadow of goal in practitioner's mind, hence the official statement that meditation has no goal. Because Buddhism aims at liberation from (among other things) deep-lying stereotypes/assumptions and implicit conceptual boundaries it necessarily involves tricks like this. Another corollary of the above, is that it's never enough to reason about these things intellectually, one needs to take them on as actual frame of reference for them to have an experiential effect.

This point is well illustrated by Dutiya Anuruddha Sutta (AN 3.128 or 3.130 or 131 depending how you count) -- the below amateurish translation is mine but here is another one.


  Then venerable Anuruddha came to venerable Shariputra and
  said:
  
  -- As much as I, friend Shariputra, try and look at things with purified Heavenly Eye, try and see things with thousandfold-superhuman
  vision, train in confidence unmovable, in awareness undimmable, in
  tranquillity imperturbable, and in focused mind unscattered, still I
  can't "having stopped maintaining intoxication, achieve liberation of
  mind".
  
  -- All these thoughts, friend Anuruddha, of the kind "I try and look at things with purified Heavenly Eye, I try and see things with
  thousandfold-superhuman vision" -- this is your conceit.
  
  And the thoughts of the kind "I train in confidence unmovable, in
  awareness undimmable, in tranquillity imperturbable, and in focused
  mind unscattered" -- this is your pathologic restlessness.
  
  And the thoughts of the kind "still I can't "having stopped
  maintaining intoxication, achieve liberation of mind" -- this is your
  remorse.
  
  You'd better, friend Anuruddha, these three dharmas abandon; To these
  three dharmas not attending, the deathless aspect assemble with mind.


Here "the deathless aspect" (amrita-dhatu) refers to Nirvana, in this context also described as vajradhatu, "the indestructible space that accommodates everything, samsara and nirvana. Nothing can challenge this space. In spite of its clarity, or discriminating wisdom, it is still indestructible." (Chogyam Trungpa)

"see ourselves as we really are", "engage directly with reality" and "grasp enlightenment" -- all refer to the same thing. This is when "compassion" happens naturally. In order for this to happen, one has to "remove wrong perceptions", "remove all entertainment and distractions" -- which includes removing the notion of goal or attainment, hence "no starting point nor goal, nothing to attain" without any trace of "eventually".