Mach and pokeys have no idea how far your machine moved. Unless your using closed loop steppers. You need to carefully calibrate each axis. Calibration means it moves an exact distance for a set number of pulses sent.
there are a lot of suggestions how to calibrate in addition to the Mach manual.
Beyond issues with backlash and deflection you shouldn’t see a difference between DRO and actual movement after calibration.
Btw if your drives are set to a low resolution it won’t exactly hit the distance requested.
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