"if there was a way to show the reasoning behind deleted submissions" I don't know why they don't do this but I can see why they might not do this. By stating

"if there was a way to show the reasoning behind deleted submissions" I don't know why they don't do this but I can see why they might not do this. By stating a reason you then invite questions around the decision and waste time in addressing those questions. By not stating a reason many decisions like this will simply go unquestioned in a "nothing to see here move along" kind of way.