@gumwars what you describe seems to be a collaboration if the handoff was to another person. I won't speak for anyone else or some abstract point of view...
If I were to do the same thing, my creation would no longer be 'mine'... it would turn into someone elses vision and interpretation, and out of my control to match what I alone see. I just couldn't put my name on it.
I have been refining 'her' for 15 years, and I'm still not done. Time invested is irrelevant.
https://lumiworx.com/albums/3d-software/content/ht-female-2017-color/
@lumiworx Do you attribute the software engineers that created Blender, Maya, or Zbrush in the creation of your work? Or are those simply tools you used to actualize your vision? Granted, a truly hardcore 3d artist could create an image using plotted points and a .CSV file, but that seems a pretty harsh hurdle to get over to "own" a particular work.