Realty Income Corporation (NYSE:O) yields around 5.5% right now. For many income investors, that number alone looks attractive.But here’s the thing most beginners miss: yield doesn’t tell you if a dividend is safe. It tells you what you’d earn if the company keeps paying. The question is whether they can.A stock yielding 8% sounds better than one yielding 5%. Until the 8% yield gets cut in half. Then you’re stuck with a 4% yield and a stock price that dropped 30%.This happens more often than people think. A ...