But first: do we really need it?
Yes. Absolutely we need it. Because purpose is necessary to meaning - our lives cannot have meaning without purpose - purpose is what enables meaning.
Purpose is the organizing principle. A so-called-meaning without purpose just reduces to a sensation, a feeling, a state-of-being - coming from nowhere, leading nowhere.
If your life has no purpose, then it has no meaning. To put it harshly - your life is pointless. This is just a fact; and it doesn't matter what you happen to think about it; it doesn't matter if you tell me you are happy, or that you don't really need a purpose... You are a free-spinning cog: going nowhere, going nowhere..
So we must have purpose, and purpose must come first.
This could, probably should, be a way of sorting-out your spiritual and religious life; and of combing-through and evaluating the multitudes of wise men and gurus and advisers which are available, which assail us.
What is the purpose of it all? - is what we need to ask. If there isn't a purpose to what is being proposed, it should be rejected as inadequate. If the purpose is lame, confused, self-contradictory - then likewise it must be rejected.
But how to compare the purposes - several religions do have a purpose, and it is coherent - how to compare them?
Ask: is the purpose adequate? Here people will indeed vary.
One may find a purpose adequate that another finds insufficient. For myself, I cannot find adequate any purpose which allows only the reality of this mortal life on earth and denies other life. All such notions seem to reduce to no purpose at all.
And on the other side, I cannot be satisfied with a final purpose that renders our mortal life erroneous and superfluous and places all value elsewhere. If Paradise, Heaven, or the Platonic forms are the only real and Good reality - then why bother with mortal life at all? We should not be messing about here on earth; we should Go to Heaven - Go directly to Heaven - Do not pass Go - Do not collect 200 pounds.
Furthermore, I find inadequate an ultimate purpose which is static and involves the annihilation of my-self. If the purpose is that the self is to be annihilated, absorbed - they why bother having a self in the first place? Makes no sense to me.
And I have no use for 'perfection' (in any absolute, infinite, unqualified sense). Happiness - yes; Healing - necessary; Joy - of course. But 'perfection' is stasis... see above.
However, different people really have different priorities for their purpose; and no purpose will be wholly-coherent and wholly-satisfying; because some insufficiencies, some unanswered questions are part of the human condition.
(The human mind, human society, can generate questions a hundred times faster than answers - because while answering one question another hundred can be generated - especially when not listening to the answer.).
But really, everybody must have one - nobody ought to be satisfied without one.
And a state of permanent distraction from the question by serial over-stimulation, busy-ness, numbness and intoxication really doesn't make the slightest difference to the reality of the situation.