Yeah, I did that a lot in my younger days. Eventually I began to work out before speaking if I really wanted to speak, if what I wanted to say was really worth the hassle, or even if anyone was interesting in hearing it. Sometimes the answer is no so I stay quiet, then when the answer is yes it's easier to speak because I'm more certain about what I'm saying and why I'm saying it. This isn't foolproof, though, as there is sometimes confusion, and self-sabotage can rear its ugly head and screw things up.