What is the purpose of proactively teaching the dog both the 'speak' and 'quiet' commands?

Answer

To teach the dog that its voice is a tool deployable and extinguishable on command

This technique reinforces the owner's leadership by training the dog to use its voice when commanded and, crucially, to cease vocalization when commanded.

What is the purpose of proactively teaching the dog both the 'speak' and 'quiet' commands?
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