Let's say you're holding a corporate bond that pays you 5.5% in interest per year. That rate seems decent and roughly in line with the typical interest rate on long-term, AAA industrial company debt over the past few years (using Moody's data).
But what if inflation is running at 5.5%? Then you're not really earning anything. The interest you earn matches the decline in the purchasing power of your dollars. Or in other words, you're simply running in place.
And if inflation is 10%? In this unhappy scenario, you're actually losing money - to the tune of 4.5 percentage points, or 450 basis points, if you prefer.
That's the concept of "REAL" interest rates versus "nominal" ones. You have to not only look at the current, nominal level of rates, but also what inflation is doing, to get an idea of whether monetary policy is easy or tight.