I'm not sure they are different. Has there been a check of the machined surface, I.E., a CMM check back to the model?
The CAD model is showing isoparm lines. That is normally an indication of a contoured (non-flat) surface.
You would not see those exact lines on a machined surface, except if there were sharp peak edges @ those lines.
The lines on the machined part are from the CNC cutting tool, probably a small ball mill.
A ball mill will leave scallops on the surface that have to be sanded out, leaving a smooth finish.
Translations could and did fail in the early days.
I haven't seen a failed translation from CAD to CAM for decades.
A CMM check will show if the surface is with-in tolerance.
Harold G. Morgan
CATIA, QA, CNC & CMM Programmer