Every writer has an ‘inner editor’.
Some writers have this internal analytical monitoring function turned on and operational all the time. Others have it switched off and barely activate it at any stage. Thus we can theorise that there are several levels of operation of this editing apparatus, none of which is ‘senior’ to any of the others - in other words, there is not necessarily a 'right' way or a 'wrong' way of doing this.
The first level is that stage in which the writer simply writes. For many writers, this is where the inner editor is totally inactive: the whole point for these writers is to get words out onto a page without interference. No checks are done on spelling, grammar, punctuation; the only monitoring that occurs could be said to be ‘raw’: the organic, unanalytic and primary guiding of the imagination as it generates images, scenes, chapters, sections and eventually a whole draft. For many, this is the act of writing in its entirety.
That first level hardly ever happens, though, without at least some awareness on the part of the editor within. Even as words rush out onto the page unhindered, there is usually a slight inkling on the part of the writer that some words are ‘appropriate’ while others are ‘inappropriate’. As the process of writing continues, this awareness can develop into moments of epiphany - those times when it suddenly dawns on a writer that, were a change to be made to a character or scene or something else in a particular way, a whole load of problems would be solved or an entirely new dimension of wonder opened up. I recall many times in the act of writing having such moments: connections occurred, links were made, ‘tweakages’ startlingly came to light. Occasionally, I would scribble these down, then, forgetting them, I would return to a manuscript months or even years later and be reading along when exactly the same epiphany would occur. ‘If I were to write this next, that would make this so much cooler!’ I would think - only to read on and find that I had written exactly what I had just thought of, only months or years earlier. What is happening here? Who knows? The phenomenon, when it happens, is wonderful: it is as though your inner editor is tracking along with you, like an invisible companion, or as if the story itself existed in some form independent of you writing it, just waiting to be ‘discovered’ rather than written.
A further level of inner editing occurs more consciously and formally once a draft is complete. Now, with a higher degree of awareness, an editor hat is placed on the writer’s head and he or she begins to read through the draft very much awake and looking at the thing in a wholly different way. Gone is the tsunami of creativity that washed this wordage ashore - now the inner editor, like a beachcomber, finds that wreckage and decides what use it can be put to. This involves much more than tidying up spelling, punctuation and grammar - this is a process, if done fully, of re-orientating the story to its core vision and message.
Gradually, as the inner editor gets to work, the real story emerges from within the draft, just as a sculpture emerges from within raw stone. It is at this level that many writers - possibly the majority - feel the burden too great: their inner editor, operating at full power by this stage, simply cannot get the required result. The clarity of the writer’s ‘inner eye’ has dimmed due to the heavy work involved of creating the draft, and they feel that they need outside help. Which is where professional editors step in.
A professional and experienced editor knows that the first task is not adjudicating changes in the manuscript. The first thing is to listen carefully to the writer: the vision that emerges should not be that of the editor but the writer. Unvaryingly, the job of the editor is to disentangle the writer from confusions or errors which have entered into the work as part of the process of writing, from the mechanical errors of spelling and so on to the more intangible departures from the core of the tale which will have occurred as the draft went along
In the end, the resulting manuscript is never ‘pure’, just as any painting or piece of music must fall short to some degree of the lofty ideal from which it sprang. But it should be as close as is humanly possible to that ideal.