Author of any kind is not an abstract "artist" from an ivory tower that receives his work from a muse in a fit of inspiration - it's just an image that helps to

Author of any kind is not an abstract "artist" from an ivory tower that receives his work from a muse in a fit of inspiration - it's just an image that helps to sell copies. He's a marketer, too. He has to sell his image and unique style. When he works, he has to imagine what effect will his work have on the audience - which is exactly a marketer's skill. Also, these "versions" of product are quite common in different forms of art. Songs have radio versions, album versions, remixes and simply alternate releases. Whole albums have different masters (released for different medium and audience). Movies have director's cuts, movie cuts, TV adaptations (where they sometime get serialized). Books composed from chapters printed periodically in magazines, with author responding to reader's feedback (which was much more common in 19th century, but still).