Transition from middle-game to end-game

I wonder if there is a clear definition in chess theorie when middle-game ends and when end-game starts. I found some ideas of a possible definition but couldn't get a clear picture till today:

1. Some people speak of an endgame as soon as the queens left the board.

2. Others define endgame by pawns starting to head towards promotion.

3. Sometimes the endgame seems to start when the kings feel save enough to leave the castled position and support the promotion of their pawns.

None of that definitions seem to be accurate enough so it is still difficult to mark the very move which ends the middle-game and starts the endgame. Maybe it is only possible to localize some kind of "transition period" ?

Don't worry about the defiinition.  Worry about the position u are looking at.

It's a vague concept, there can be no accurate description.

 Don't worry about the defiinition. Worry about the position u are looking at.

So there is no clear definition but only a vague concept.

Amazing that everyone is using a term but noone is able to define it clearly ....

Why do you need a precise definition? Just play the position on the board...

You're in an endgame when the main strategic goal of at least one of the players is to promote a pawn.

One of my clubmates used to refer to candidate passed pawns for the coming endgame as 'retirement points' 

"You are in an endgame when the main strategic goal of at least one of the players is to promote a pawn"

With "strategic goal" any tactical middle game positions with posibilities of pawn promotion are ruled out.

That looks definitely better than the definitions I had before. I like that.

Thanks hicetnunc

I was taught it was when you are down to about 13 points of material apart from pawns but that seems flawed as obviously for example queen and rook vs queen and 2 minor pieces is no longer a middlegame.

Language is nearly always woolly rarely precise. We must remember that queen endgames are often spoken about and that most players have a  good idea of what the word endgame implies.

The other great difficulty is that as soon as you make a ridged definition some smart Alec will find an exception. Players often talk about exchanging down to a favorable end game and most of us know what they mean.

As for the very move that marks the transition its just not possible.

You can't seperate tactics from strategy.  In the middlegame where a passed pawn is across the middle for exampe, it may be a dominant strategic theme for quite some time.

Pfren's post sounds very familiar, but I coudln't find it in the book I thought it came from. 

You know you are in an endgame when the work of your major pieces shift their emphasis from weakening your position to moving in for the kill - without going for the king... and more importantly you know you are in an endgame when your eyes start to feel tired and - although there are no forced mates in the offing - your heart starts beating that way over the safety of a single pawn.

Yes - and you also know that you are getting old

Look this video and You´ll know when the Endgame begins ! 

Maybe this scene explains the term "desperado", too :  

Yeah - there is nothing compared to a last stand before resigning

endgame started from the point u try to capture queen and king opponent

Has Winnie_Pooh been here since 2012?