Hi. It would be useful to be able to have rsync warn or die if a file is not transferred due to --update. The use case is that if you're intending a source to be a "master source" for a destination, you want to be told in a proactive manner if a (non-excluded) file has actually been edited at the destination. Thanks!
Pass -vv or --info=skip and you will get a message, "FILE is newer".