That headline comes from warnings issued to Americans during the World Wars of the last century. It was a reminder that sensitive data that was discussed publicly could be overheard by those working for the enemy. Military and diplomatic history is full of tales in which a careless remark doomed a battle or other operation.
The same holds true for the business world. In my ad agency days, I remember working on a hard-fought effort to keep a large client. Several people in the organization’s marketing department disliked my agency’s team and hoped to replace us with another shop that employed their friends. The run-up to the selection involved weeks of late hours and anxiety, because job cuts invariably follow the loss of a large account.