The most important way of ensuring the mentioned ability to disclose is the protection of people willing to blow the whistle. One of the possible reasons for not blowing the whistle is the fear of retaliations, mostly the fear of being fired, or be pushed to resign. Other barriers for whistleblowing are legal restrictions. Nearly every company has strict rules for employees concerning the duty of loyalty and confidentiality (business secret, trade secret).
Of course not every act involving the disclosure of exclusive, hidden, confidential or secret information may be considered whistleblowing, since it has its unambiguous characteristics and rules: whistleblowers reveal information by their own will, selfless (without any personal interest), and/or because of their commitment to public interest and public good. Another initial requirement of whistleblowing is that any kind of disclosure has to be made in good faith.