Why keep a dog and bark yourself? - Proverb for January 15

The lesson from today's proverb "Why keep a dog and bark yourself" is that we should not do the work that someone else has been hired to do. The idea here is that if you have a dog to protect your home and valuables from intruders, you would not be the one barking to scare them off.  You would let the dog take care of this task which is it what it has been trained to do.  Another example would if you have hired someone to clean your house but before the housekeeper gets there you run around and tidy it up first. 

As I think about this proverb I see another angle this proverb can take.  If you have a dog and you end up having to do the barking yourself, there isn't much use for the dog.  I think this would apply to work and other group dynamics where someone does not pull their weight and causes the others to pick up the slack.