Hey there.
Due to the nature of how 3D printing works there can be shrinkage on ID of holes. As it's extruding in a circular motion the material tends to pull inwards.
A lot of people design parts and add .2 or .3mm or so for holes in their designs to cater for this.
Now there are features in cura like hole horizontal expansion to help make it more accurate.
There are many factors that can alter the accuracy. Speed, temp, material etc.