In the realm of laser powder bed fusion, an emerging field with significant growth potential, we still find ourselves at a pioneering stage characterized by the intricate interplay between laser beam properties and their interaction with powdered material.  It is commonly assumed that a high-quality laser having a low M² value would maintain a consistent M² value uniformly across the build plate.  However, contrary to this assumption, variations do occur across the build plate, not due to fluctuations in the laser's M² value, but rather due to alterations in the beam's geometry.  Even in scenarios where the F-theta lens or the 3-D galvo system operate at diffraction-limited conditions, the reality persists that a Gaussian beam with a low M² value positioned at the nominal zero-zero point of the galvo system will inevitably lose its circular profile at positions beyond the zero-zero point.  At non-zero angles, the beam undergoes distortion, presenting itself to the powdered material as a conic section of the single-mode Gaussian beam.  Employing an innovative M² measurement apparatus, we have quantified the M² variation inherent in a fiber laser galvo scanning system across a scan field measuring 175mm x 175mm.  This understanding of the M² variant holds significant promise in facilitating the stabilization of an optimal spot size.  Through dynamic focusing adjustments based on the powder bed's positional information, we can effectively compensate for the observed variance, thereby enhancing the overall performance and reliability of the laser powder bed fusion process.