Interpersonal Communication Is Inevitable....We cannot
not communicate. In addition, you cannot
not influence the person you interact with. Persuasion, like communication, is also inevitable.
Interpersonal Communication Is Irreversible and UnrepeatableNotice that only some processes can be reversed. For example, you can turn water into ice and then reverse the process by turning the ice back into water. Other processes, however, are irreversible. You can, for example, turn grapes into wine, but you cannot reverse the process and turn wine into grapes. Interpersonal communication is an irreversible process. Although you may try to qualify, deny, or somehow reduce the effects of your message, you cannot withdraw what you have said.
Because of irreversibility, you have to be careful not to say things you may wish to withdraw later. Similarly, you need to monitor your commitment messages--the "I love you" type messages--carefully Otherwise you run the risk of committing yourself to a position you may be uncomfortable with later.
In addition to being irreversible, interpersonal communication is also
unrepeatable. The reason is simple: Everyone and everything are constantly changing. As a result, you can never recapture the exact same situation, frame of mind, or relationship dynamics that defined a previous interpersonal act. For example, you can never repeat meeting someone for the first time, comforting a grieving friend, or resolving a specific conflict.
(from Joseph A. Devito's book, "Messages: Building interpersonal communication skills", 3rd edition)