I finally discovered it when I saw your explanation on this forum. Prior to that, it made zero sense. An error message that requires an internet search to be understood is a poor error message. I spent quite a bit of time trying to recreate the circle and then adjusting my inputs to see if I wouldn’t get the error, then finally gave up and started searching. When that didn’t work, I came here, and managed to find the explanation.
Why do I need a small diameter with so many sides? Because the large diameter circles that I was drawing beforehand were fugly without increasing the number of segments. Having successfully drawn larger diameter circles, then getting an error when trying to create a smaller version of the same circle and getting an error that doesn’t explain itself is eminently frustrating.