"There's all the difference in the world between having something to say, and having to say something."- John Dewey.
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You must not be seen as saying something because you want to but because you really do have something to say.
Having something to say is way different from having to say something. Pick that which is important and needed for you in this race of life and stick to it.
The power of speech is what defines what we do as individuals and as a people and no matter what we do, results will be based on how well we understood what we have with us and what what we have can do for us.
"Seeking first to understand as we hear the words of life flow from others to us" is the most important step anyone looking to prosper can do to help themselves.
Speaking is an art and it is the reason why some have made and are still making a living doing it. These kinds of speaking is called motivational speaking.
So before you say something, do yourself a favor and say it because it means something and not because you feel the need to yap.
Apply the art of speaking motivationally and you will discover your are smarter than you always thought you were.
Don't bother to speak, save your voice for when there is nothing to speak and speak when it is entirely necessary to and you will have used your vocal skill profitably.
"He spoke out of turn", "he spoke nonsense" is one common word we hear daily and those who do these are those who speak because they want to be heard for whatever reason.
For the empty speakers, their motivation to speak is unguided and lacks the right push because it all comes down to a fail.