" 
 ::, there are thousands of talk page discussions going on every day on Wikipedia and most of them come to a natural conclusion and aren't formally closed. Some exceptions to this is that some editors like to close (hat) conversations on their talk page once they are finished, RfCs that are trying to come to a decision regarding a content or policy issue can be closed by an uninvolved editor or admin and often cases brought to WP:ANI and WP:AN are closed once the situation is resolved.  
 ::Often, you can end a discussion by simply stopping your participation. No one needs to have the last word at Wikipedia, if the issue arises again, a new discussion can be started.    "