Once I worked for a company that got a quote in the form of a Word document. Turned out it had history turned on and quotes to competitors could be recovered.

There is a lot of incompitence when it comes to file formats.

I think it's more that the analogy is broken.

If I have a sheet of paper and I color a section black. That's it. It's black. No going back.

So I can see people thinking the same for PDFs. I drew the black box. It's black. Done. They don't realize they aren't dealing with a 2D sheet of paper, but with effectively a 3D stack of papers. That they didn't draw a black box on the page, they drew a black box above the page over the area they wanted to obscure.

The fact that this happens a lot is an indication that the software is wrong in this case. It doesn't conform to user expectations.

I'm sure not all those hundreds have been involved with every document.

I'm kinda surprised (and disappointed) nobody has done a Snowden on it though.

Having lots of people involved means that it's more likely to be malicious compliance or deniable sabotage. It only needs one person who disagrees with the redactions to start doing things that they know will allow info to leak.

> Since hundreds of people were involved the most likely explanation is incompetence

Hundreds of people might be involved, but the only key factor required for a single point of failure to propagate to the deliverable is lack of verification.

And God knows how the Trump administration is packed with inexperiente incompetents assigned to positions where they are way way over their head, and routinely commit the most basic mistakes.