This might be as designed because reasons, but I'm not sure. If there's a report in the report center for, say, spam and you delete the content with the offending content before even viewing the report, if you go to the report center, the report will be closed. This happened to me just now, but yesterday it didn't happen, unless I did it differently, so I can't seem to get it to happen consistently. Either way, I can see this being a minor issue for those who want to take care of the offending content first and then notify the reporter it's been taken care of. Pretty sure I disabled add-ons and all that when testing this.