I migt not remember this perfectly but I heard this story when I was a child

A man had a guard dog. The dog barked when a thief came by so the thief left. The owner hearing the dig bark but seeing no thief punished the dog for barking when there is no thief.

A thief came another day and the dog would not bark to avoid being punished. The thief stole the dog owners things and the owner punished the dog for not barking when there was a thief