What are the biggest mistakes people make with Medicare?

Once you know what pitfalls to watch for, navigating Medicare becomes significantly less daunting. Mohamad Faizal Bin Ramli/Getty Images

Every year, millions of Americans navigate the complex world of Medicare enrollment, and every year, countless people make preventable mistakes that cost them money or leave them with inadequate coverage. With more than 69 million Americans enrolled in Medicare currently, and with thousands of baby boomers becoming eligible each day, a significant percentage of Americans rely on this type of coverage to keep their medical costs down during retirement. What many may not realize, though, is that the stakes are high in terms of getting Medicare decisions right the first time.

That isn't always easy. The program's alphabet soup of plans — Part A, Pa