QUOTE(Wikiquote Last Words Article:)
Go on, get out! Last words are for fools who haven't said enough!
Who: Karl Marx, asked by his housekeeper what his last words were.
If writing one makes you feel at peace, then do it. If you're writing it to gain recognition, then it's a pointless waste of paper.
The only significant effects such a document would have are to put your mind at rest, and perhaps bring some sort of consolation to your loved ones.