What is the difference between a chess master and the average chess player?
There are quite a number of aspects that separate the two but the most commonly occurring difference is the ability by the master of the game to understand the various elements of a given position.
At a glance, he quickly analysis the general position; then he decides on the immediate plan of action either to consolidate an advantage gained in the opening, to improve his inferior position or to counter a kingside attack by attacking on queenside through the center etc.
While this is the case, one very interesting outstanding difference is the ability to convert an inferior position into a won game. This could either be in the middle game through tactical combinations or in the end game - where he forces positions which appear lost at first into wins or at worst draws.
The average player on the other hand is unable to convert an advantage gained early in the game into a win through lack of clearly defined plans at a particular time in the game. Perhaps the most disappointing part of it all is the fact that sometimes he doesn't realise that the advantage has already been lost.
Most games are won in the middle game but you must know something about the endgame. The endgame is essentially strategic, as the rest of the game should be, although tactics may obscure this.