I have published over 2300 pages of technical books, and over 1000 pages of technical papers (conference and journal papers), and if there is one thing I am certain (for me, at least) it is this: writing is editing. Far far more time is spent on editing drafts than initial writing. It is inconceivable that I would or even could write any thing technical from beginning to end and not have to edit it many times.
That being said, it is true that a scholar may get caught up in finicky editing rather than more substantive scholarship and thought, so the question arises when to deem a paper "finished." Often a conference publication deadline dictates the point. Occasionally it is the knowledge that a competitor is about to "scoop" you. Sometimes it is the desire to move to a new topic or new paper that dictates the point.
My personal recommendation is to get the feedback from the most critical and knowledgeable colleague or scholar on your paper, and when he or she says it is ready for publication, go with that.