Why aren't double quotes always closed? [duplicate]

When a quotation is more than one paragraph long, double quotes are placed at the beginning and end of quote and at the beginning of each paragraph. The unclosed quote serves as a reminder that you are still reading a quotation.

A paragraph that begins with a double quote should also contain a closing double quote, or be followed by a paragraph that also begins with a double quote.

Double quotes are closed at the end of the "speech act". As long as the same person is speaking, each new paragraph starts with an opening quotation mark, but the closing quotation mark doesn't happen until the person is finished speaking.