Curvature Analysis: Max Radius vs Min Radius




I am using Curvature analysis from Rhino 5. I have two quick questions about the difference between Min radius and Max radius in the curvature analysis. If you have any idea, It could be of great help!

Curvature analysis manual:
What I understood is Min radius and Max radius try to capture curvatures at a point regardless of the principal curvatures. I couldn’t catch any difference between those two “Min radius” and “Max radius” from the help manual.

According to the manual, “Max radius” is useful for flat spot detection, and “Min radius” gives us the min radius of surface for cutting ball --> both are measuring curvatures with the min (blue in legend) and max (red in legend) at a point regardless of the princial curvatures. Then why they are called Min radius and Max radius??

Thanks in advance!