Target Readership?

I am quite new here. I have been reading for the past couple of weeks
and love the responses to questions you fols have been giving. So, I am
sucking it up and venturing to post a question of my own. I am not sure
if my question will be clear enough, I am having trouble phrasing it,
but.....

When you begin to write a story do you write it to a target reader base
from the start or do you just write what comes and let it form it's own
"readership identity" (for lack of a better term)?

Thanks,

Dawn
www.sun-wolf.com

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