Just a few comments:
Film based photography required a print, more highly valued if made by the photographer. The print varied over time, see Saint Ansel, and how his prints evolved.
Now, with digital, it is the same; software evolves, so the "artist" looks at his digital files, and improves them, and makes prints that are different, from his first set. Printing technologies change, sometimes for the better, sometimes not. And anyone with a serious interest in the interaction of the file from camera, software to process, and printer/ paper, knows that controlling all the variables will not guarantee duplicate prints if one of the little variables has changed. Upgrade your computer software, your prints might change, indeed, probably will, and you might never be able to get back to where you were.
I value things as follows:
a. A piece done by hand where there is no ability to produce an exact replica, other than making a copy of the original, which would be "a copy".
b. A print, either etching, engraving serigraph, etc. etc. including photos from a wet darkroom, and digital prints,
done by the artist. The quanity produced isn't that important, as if the artist did it, they are limited. They are called
prints, for a reason. Prints.
c. Copies made by craftspeople other than the artist, and we're not even going to mention the way sculpture has been done. That is where there is a lot of gray areas. Phew!
d. Photo-mechanical copies made on printing presses, signed and numbered, and as about as far from the hand of the artist as can be, unless they actually signed it. Maybe?
And, I'm just as confused as when I started blathering ...
