Set up a guitar route and the routings measure 2 mm less then numbers programmed what is causing this.
Need more input. Sharing the project in Easel is good.
Machine calibrated? (Does it jog 250mm if a 250mm jog command is given)
End mill true in size?
Backlash?
System flex / lack of rigidity?
Work flow error? (Conversion issue or cut set to follow path vs inside/outside cut)
Outlines such as that are usually set to cut outside of path.
Pickup routes set to inside path?