If it's that bad all over, yes. FYI, a floor is inspected from a standing height, generally quoted as being 50" away, under normal lighting conditions. Floor sanding is a process of making the wood flat and smooth by using progressively finer grits. Beyond a certain point, the wood can be sanded so smooth that it doesn't accept stain. Because of this, you'll likely always be able to find minor scratches on any stained floors, but there's a limit to how many are acceptable, so occasionally there can be a gray area on what's acceptable. If it's truly "all over", it's likely that the finisher will tell you they need to start over. If it's not too bad, but really bad in a critical area, do over. If it's generally good and there's a few spots like this is less consequential areas it might be best to leave it alone.

Thank you for your input. There is a significant amount of this scratching. I will see what he says tomorrow.

Great news!

It's more likely to be grit walked in that got under the buffer on the final fine sanding. The worst parts of being in this business are that you can't see things like this until you stain and that what's a relatively minor cosmetic flaw can trigger having to do a significant portion of the work over.

Good luck!

He did mention something like that. He said it’s hard to know exactly what caused the issue but hopefully won’t happen the second time around!

Is there any harm is doing this entire job again? Is it bad for the wood to sand all over again?

It's slight. It's already flat and going back the same color, so the amount that's necessary to sand off is rather minimal. Floor refinishers don't want to sand any more than necessary, so they start with the finest grit that will remove the existing finish.

Floors have been sanded and stained for the second time and there are no more marks! Thanks everyone for your advice