Words once spoken cannot be taken back. Often either in our excitement or in jealousy we shoot darts of dark secrets out in the open. Also, we gossip about others. Is there a guarantee that the words you spoke loosely about someone will not reach the same person ? There is no guarantee. And when it does you have created a new enemy.
People maintaining silence often also are able to better absorb the surroundings & morever connect with themselves better. We often think words are a mighty weapon but indeed silence is mightier.
Silence saves you from regret !