The operation mode differences in below:
Classic：
15 frames / sec
Direct scan with selected resolution
Good for: small parts, middle resolution scan.
Lightning：
30 frames / sec
Scan with 1mm resolution
Interpolation to selected resolution when end scan
Good for: large part with low resolution scan
Lightning + Refine：
30 frames / sec
Scan with 1mm resolution
Parallel capture of frame data
Refine to selected resolution after scan, by retopology, using the frame data
Good for: large part, allow recalculation of the resolution.