Logwatch Broke Today

I logged into my email to check for my nightly logwatch report (at 12am).
Nothing.

So I log into ssh and manually run it, get greeted with this:

You have old files in your logwatch tmpdir (/var/cache/logwatch):
logwatch.zcTV3hC0
The directories listed above were most likely created by a
logwatch run that failed to complete successfully. If so, you
may delete these directories.

I last ran logwatch around 10:30pm, it worked fine.

I try to run logwatch again, same error.. except now there's another temp file showing beneath the first.

I go ahead and delete both of them, run logwatch again...it worked. I also got the other reports from when I tried running logwatch manually and was stopped with this error.

I've never had this happen before, so I'm curious as to what caused it? Logwatch is in cron.daily and has never missed a single report.

Just typical data corruption (as can happen with any computer file) or could something have interfered with its processing at 12?