I assume you don't have a dog?
Dogs get excited when they hear certain words they are familiar with (like "walk") so in order to avoid all the barking and whining you sometimes gotta do this. At least, that's how I understood it.

Pretty much this. Though it gets worse when they learn how to spell, then you have to develop new code words and terms and change them whenever the dog learns to descripher them. Dogs are a lot like spies.