Cylinder Fit Data Window
The Cylinder Fit Data window gives realtime feedback for the quality of the fit of all the surface points to the cylinder centerline.
This gives assurance that the measurement was a good one.
The key values in the window are the X and Y values. Think of those two values as the "wobble deviation" of the cylinder fit from the surface points on the cylinder. If you see the wobble grow too high, then you can expect that the measurement is not as accurate as it should be.