I’ve never been entirely sure what voice is, while at the same time I feel it’s something I know in my bones, unique as a retinal print.
As a writer, my voice is part of me. Yet it’s not static.
The time my voice comes out most is when I’m not focusing on craft (tools of writing). However, I don’t think voice can clearly emerge unless the craft elements are already in place. When word choice and rhythm and flow are happening on the unconscious level, I think it’s easier to see the voice that’s present. Also, I think a writer’s voice is often strongest when she is writing about something important to her, especially when it’s of emotional importance. The extra commitment comes through on the page.
We can refine and strengthen our own voice in revisions just like anything else, if we know how to recognize it.
I feel voice is something that grows and changes as your skill with writing tools grows and changes, and as your topics change.