They move a few inches per minute, so it's easy to ignore the irrelevant slug that is nearby but not over the button.

IME they tend to leave a lasting conspicuous shiny trail....

You could probably see there was nobody there without going outside and check the doorbell panel. So they would come to the conclusion they were too late to catch the little brat

That still makes it at best a fun story to tell during family dinner, not on international press.

Why is this on hackernews in the first place...

Slugs could probably have beaten the police response time in my country.