Automatically Generated Reformat Planes in 3D Slicer

The image below shows a screenshot of the reformat plane generated automatically by 3D Slicer. As you can see, I haven’t made any changes after loading the DICOM file. However, the generated reformat plane appears rotated and tilted relative to the 3D cube frame.

My questions are:

  1. What criteria or principles does 3D Slicer use to generate these reformat planes?
  2. Why is the reformat plane misaligned with the 3D cube frame, as shown in the pink lines?

I’d appreciate any insights or suggestions to better understand or resolve this issue!