Once, long ago, I received a manuscript for a book I was formatting. The author/editor had used Track Changes in MS Word, without, at the end, “accepting” all the changes. So I formatted the book, which ran rather long, not with the manuscript, but with every iteration of the manuscript imported into the page-assembly file.
They should have known better, but they were oblivious to the automatic feature, and like so many people, did not properly understand how the tools they were using worked.
Today I learned that the default behaviour of some applications, TextEdit for example, is to autosave any changes you make, but keep EVERY version of your files in a Revert To menu. “A Modern MacOS just keeps the changes by default,” These kinds of paternalistic hand-holding features are a trap for people who are begging to have a version-control nightmare. You need to manage your versions of files consciously and actively.
When editorial got a look at that first-pass I had formatted they spit out their drink. But I had formatted the manuscript file I was given. The formatter cannot be editing the supplied manuscript. So, they had to resupply the Word file WITHOUT every version embedded in it, and they paid me to format the whole book… again.