Cave Art Is Incomplete Art

" is incomplete without the perceptual and emotional involvement of the viewer..."beholder's involvement"." (Riegel 1950's).  "beholder's share" (Kris and Gombtich 1950's).
"...the viewer responds
...  in terms of this or her own experiences and conflicts..." thereby participating in the creative process.
Reductionism In Art and Brain Science, Eric R. Kandel 2016.

Do you ever feel something is missing from your artwork that remains private?