Van Gogh didn't develop in an artistic or cultural vacuum. He received lots of criticism over the years and worked with the Parisian avant garde. He had peers to receive feedback from.
True artists ship to real artists..“Make things that people who’d like to make things people want want” (Like this Website). The unreasonable effectiveness of higher order recommendations.
His roommate the successful artist Paul Gauguin? Tried to borrow Sunflowers but
“Van Gogh was upset and replied that Gauguin had absolutely no right to make this request: "I am definitely keeping my sunflowers in question. He has two of them already, let that hold him. And if he is not satisfied with the exchange he has made with me, he can take back his little Martinique canvas, and his self-portrait sent me from Brittany, at the same time giving me back both my portrait and the two sunflower canvases which he has taken to Paris. So if he ever broaches this subject again, I've told you just how matters stand".