Bad language is not only bad and harmful: it is also ineffective; it is fraudulent. Speaking badly means not making yourself understood; and those who don't understand don't trust. He thinks there's deception behind it, that you're there to cheat him. Therefore a speech, whether written or spoken, must be the first thing effective, hit the target, convey exactly the message you want to communicate. It must be concise, get straight to the point, without getting lost in boring premises or turns of phrase that only serve to fill gaps that, instead, would be better filled with useful content, or not filled at all. Because, you see, it is important to save money. Economy of words, but also economy of concepts, when they are not needed. Therefore, in addition to being concise, a speech must be economic.
And to be at the same time economical but effective there must be the right words in the right place, and the right phrases in the right place. The discussion, therefore, must be also accurate. Remember precision, it's important. Not just when you write, but always.
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