Whenever you have the opportunity to speak, the most valuable ten seconds you can possibly spend isn’t spent on collecting your own thoughts or deciding what phrasing you want to use. It’s the ten seconds spent taking a quick mental inventory of who can and will hear you.
You will save yourself enormous headache and heartache by knowing who’s listening when you speak (or who’s reading when you write). Sometimes you’ll realize the answer is “nobody,” and you’ll save yourself time. Other times you’ll note that there are far more people within literal or figurative earshot than just your narrow target. All of these things matter, and they matter far more than just what you were so keen to express.
Just as you should never fire a gun without knowing what’s downrange, you should never speak without getting an idea of who’s listening.