Let me be the first to say that I don't have an eighth of the woodworking skills you folks have. I've been working on this myrtlewood bandsaw box and fighting the finish for several days.
I can't get the scratches out. I'm sanding with 400 between coats of poly. The scratches were much more pronounced with the Minwax PolyGloss wipe on. I switched to a wiping finish of 50 % poly/mineral spirit and the finish is much better. I've tried not random orbit, hand sanding and steel wool. I still have visible scratches.
Disreguard the dates on the photos, I'm no better at camera work than finish work!