"Paperwork errors" can cover a fair amount of ground.
I do, however, find it curious that our government is more than willing to put firearms dealers out of business over "paperwork errors" that did not result in any actual harm suffered to anyone while turning a blind eye to banks committing "paperwork errors" that result in people losing their homes.
Should dealers be careful in their paperwork? Sure, but this is an industry that is treated much differently from any other. If you make an error, willful or accidental, in most others it's just a paperwork error. If you make any kind of violation with a firearm they treat you as though you're planning to immediately go out and start murdering people.