Eisner mentioned he was uncomfortable calling Kirby someone with heavy artistic intent. I paraphrase, but Eisner felt Jack was mostly
concerned with hitting his page count, telling good stories, and
keeping his family fed. Not pursuing some aesthetic ideal - to seek
that motive in Kirby's work was, he suggested, misguided. I happened to be holding the original artwork to the Devil Dinosaur #4 double-splash, which I turned around and showed Eisner - who took a moment, and said something uncharacteristic: “Okay, I might be wrong.