Since I understand very little about painting, am I correct in understanding that you are saying that she is very technically adept, but not good at creating art per se. I guess an analogy would possibly be that someone can be a great pianist and play all the notes exactly correct but doesn't understand how to play the inflection of the notes correctly?
more like: someone can be a great pianist but not necessarily a great composer, someone can be a great coder but not necessarily a great software engineer...
It's those additional stacks of human interface skills above a specific craft.
I've spent quite a lot of time in graduate art training and I'd go further: this isn't about a high level of technical skill or performance, it's about personality. A composer is not a pianist writ large; a software engineer might be a coder working at a high level of abstraction. But an artist is someone who works with their whole personality, engaging with the craft of painting (in this case). To have a "whole personality" that is compelling is very rare, and it's not something that happens by stacking up skills. It might manifest through an appearance of highly analytic vision or graphic composition but it is not quantifiable in those terms. It has to do with wit.
I'm going to cheekily (not in a sexist way) link this to something said by the fashion photographer who discovered Melania Trump, because I think it is exactly the same ineffable quality that is under discussion:
'Jerko thought at first that Melania had a very good future in modeling but after two sessions, he lost enthusiasm.
“Her exterior was very good to be an excellent model, but she lacked energy, a certain charm that if you have, you transmit it through your eyes, through your personality. If you have something that, shall we say, comes from the heart, it shows in the photo,” the photographer said.'
Yes... thats pretty much exactly what I am saying. I would say that one thing she lacked is a consistent sense of self. Her work was stylistically diverse. Though some artists (e.g. David Bowie, Gerhard Richter) can get away with this, for her it comes across as an uncertainty of self.
Another thing was that she was very well trained in the academic tradition. This gave her a set of skills which she could not un-learn, but were at odds with the spirit of the time. Another artist mentioned in this article was Henri Fantin De Latour. He was similarly skilled, but was also deadly focused on still life as subject matter. Though he was never a hip impressionist, still-lives were very much in agreement with much of the impressionist 'project'.
She's a massively technical guitarist - she can shred as hard as any man.
But some of her songs have a high-frequency "girl sound" (I give her male guitar tech equal blame) instead of a "brown sound", and her albums don't sell.
Having said that, her live concert version of Michael Jackson's "Give in to Me" is stunning:
