The Gemora in Megila teaches us "A word is worth one coin, silence is worth two".
The seemingly greater value of silence is apparent.
However the Chazon Ish challenges that thought. He comments "If one is to be silent from sunrise to sunset he only earns two coins, but for EVERY word he earns one coin,hence making the value of speech greater".
The Chazon Ish goes on to explain that Choosing what NOT to say is really the avoda of speech as opposed to total silence.
That's why EVERY WORD earns a coin, making speech albeit proper speech of greater value than silence.