This Bloomberg article tries to answer the question of whether art or stocks make the better investment. It does that by using the prices of two prominent paintings. The conclusion is that it depends on when a painting was purchased.
And yet! There are always, and will always, be external factors that affect the price and performance of an artwork, and that’s the point. Knowing that there is inherent volatility to a market is not the same thing as discounting the results of that market. Whether a painting was sold on a whim or under duress, is ugly or pretty, is “good” or “bad,” probably doesn’t matter to whoever sank $65,000 dollars into a painting in 1962.
What matters, and still matters 55 years later, is whether that purchase was an act of prescience or extravagant folly.