Very soon after he started releasing his work, he gained almost a cult of art appraisers who valued his work and "hyped" up his work. If one of his pieces was unfinished it showed what would be a a step in his process of creating a masterpiece and people saw value in it. I think it would be neat to have one of his unfinished but if i had to choose between a finished and unfinished i would definitely take a finished piece, i prefer my art to be completed since anyone can half ass a painting.