Those lured by the quick-profit possibilities of the stock markets should heed a cautionary tale that’s playing out. In a nod to the herd instinct that often leads the market by the ear, the price of Parle Industries—a small-cap stock representing a real estate company—has been hitting the daily upper limit of 5 percent for four consecutive trading sessions up to Monday. The buoyancy follows the Indian Prime Minister’s jocular reference to the toffee brand Melody—close to the popular portmanteau of the Italian PM’s name and his—which is manufactured by an unconnected, unlisted company called Parle Products. Whether it is a play by shady operators or a genuine confusion that has persisted despite clarifications, investors should take the stock phenomenon as a bitter pill, not a sweet snack.