"Wicked leaks" from your organization are most often revealed to customers both verbally and non-verbally. This is just like the infamous “Wikileaks”… only these leaks are about you and your business.
Your disgruntled staff’s “tells” are given away with looks, glances, rolling of the eyes and outright truth-telling. The most dangerous employee is one who is assisting your competitors by driving your business away. They are not loyal to your organization... only loyal to themselves.