Before the 20th century, the "Mona Lisa" wasn't even the most popular painting in the Louvre. But in 1911 it was stolen, smuggled to Italy and exhibited widely before being returned to France, whereupon Marcel Duchamp defaced a reproduction of it and labeled his work with an obscene pun. The painting rocketed to fame, its pigments and brushstrokes unchanged. The "Mona Lisa" is the artistic equivalent of the investor who did nothing special until he got lucky a few years (or quarters) in a row and was fêted as a genius. Ecclesiastes told us that time and chance happeneth to all, but we easily forget.
--Christopher Chabris, WSJ, on the vagaries of taste and fame