As mentioned in the article, there's always potential downside to preferred stock. A more accurate comparison is if you could buy Twitter stock for $100, would

As mentioned in the article, there's always potential downside to preferred stock. A more accurate comparison is if you could buy Twitter stock for $100, would only start losing money if it went below $30, and would only start making money if it went above $100. If that is starting to sound like a crummy deal, then clearly the preferred stock price has some loose relation to that of the common stock.