Dimensions and 3D printing

I think I figured out how to use dimensions better by selection the individual lines within my part. Anyway, I circled the two parts of the photo that shows what the dimensions are in Shapr3D. The hole in the photo should be 10mm but it prints at about 18mmDB615F8B-7248-4208-A732-1E38F15E38D5 . Is this a bug or am I not understanding Dimensioning?

Radius 10mm, diameter 20mm

That may be due to the calibration of your 3D printer,
adjust the motor steps, and also the extruder steps, it may be removing more material and therefore does not fit your design dimensions,
If I want to print a hole that has 10 mm I have to add 0.15 more for my object for example and then polish it a bit.