A story is usually built up. Forget about the myth of the person that has a complete story in mind, it's possible in a best case scenario but quite unlikely. How often have I read a story that changed tone as you feel the author found the right passage along the way! This is where you see a good one. Having been trained as an artist I can see similarities in the creative process necessary for the building of a story. We have all heard of the X-Ray shots revealing different compositions underneath the finished work of a famous artist. Remembering this gives insight to any longwinded undertaking.
Thankfully for newbies, we have word processing to permit a more deftly concealed rewriting! Remember the old movie where there is a garbage pail full of crumpled paper?
In conclusion a stone mason friend of mine - aged gentleman - told me one day. " You can see a good cabinetmaker in the way he hides the defects he created ".