Slightly belated reply, but I think we have most commonly found 'accidental' deletions actually comes from marketers misunderstanding how the scheduled unpublish feature works. Someone in the client's marketing team commonly seems to like to schedule an ad campaign to only go on their homepage for a limited time. So their approach to this is to set it to auto-publish the updated homepage at say 9am then auto-unpublish again at 5/6pm or midnight. Except auto unpublish is not just 'taking down that advert change' it's taking down the whole homepage and everything else beneath it. And as they set it to auto, they've usually gone home when it triggers and aren't around to see the impact and immediately republish it!