Most games ARE decided in the opening.

Take this one--Nakamura LOST because he played the unethical wayward queen opening.

Most games are decided in the middle or endgame, not in the opening. 

But you know that 

lol... now that he's won the WCC, it's fun to look back at these earlier games and think, wow, the World Champion used to do s%$t like this?

Most games, below master level, are won in the first 20 moves.  

Nakamura's position looked OK until he castled Q-side. That might have been a bit over-the-top.

he lost because of sacing to much stuff

True, bad opening. The result was a foregone conclusion as the opponent found the refutation of 2. Qh5. Now, to memorize it, including all side-variations - that's another thing.

I don't think there is a "refutation", not in the sense of "Black wins".

Equalizing is no problem against that opening, though. Perhaps even a shade of an advantage for Black.

I was joking. I was going to add another paragraph to make it more obvious. I was going to say that "by move 87 white was already completely lost". 

So you're asserting that the influence of one poor opening on the outcome of a game is representative of the influence of all openings ever on their games? Yeah, good luck with that one.

The only time a game can be won is the end game, opening advantage means nothing if you cant convert it

Take this one--NE7 LOST because he played the unethical wayward queen opening.

LOL. It was so funny chasing the black queen.

https://www.chess.com/echess/game?id=130145556

So... in a Fool's Mate,does the endgame begin on move 1 or move 2?

Games are lost in all sorts of way. I do agree that the opening is very important at all levels. Its critical for a super gm. But all parts of the game are (Da). In a number of games by GM"s you will see played geared away from Opening theory towards tactics. Some like to play Opening Theory Main Lines.

"... A remark like 'games are rarely decided in the opening' does not really do justice to the issue. ... even if an initial opening advantage gets spoiled by subsequent mistakes, this doesn't render it meaningless. In the long run, having the advantage out of the opening will bring you better results. Maybe this warning against the study of openings especially focuses on 'merely learning moves'. But almost all opening books and DVD's give ample attention to general plans and developing schemes, typical tactics, whole games, and so on. ... For almost every player, the best advice is to simply study what you like most. ... I do think that some trainers overrate the benefits of studying endgames and act in a somewhat patronising way by advising us to study the endgames we might never get on the board, instead of the openings we are sure to have on the board all the time. So if you do not enjoy studying endgames, there is no reason to worry too much about it. This, after all, is what 'no-opening-theory' trainers advise us, albeit with the subjects changed: they want to let us play the opening on insight alone, but the endgame with exact knowledge. So you might try it the other way around. ..." - IM Willy Hendriks (2012)

I caveat in a game between competent players