How to find the mistake and the turning point in a game
A practical way to tell an inaccuracy from a decisive mistake and to turn a review into training.
Look for the change in chances
The turning point is the position after which your side lost a noticeable part of its chances. It can be a dropped piece, a missed tactic, or a quiet move after which your plan stopped working. Watch the size of the change after a specific decision, not only the final evaluation.
Begin with the first cause
The last mistake often only finishes a game that was already hard. Walk back to the first moment where you had to defend without a clear plan, where king safety got worse, or where one piece dropped out of play for a long time. That moment usually teaches more than the obvious blunder before mate.
Separate calculation from choice of plan
If you missed a short blow, check your habit of looking for checks, captures and threats. If there was no tactic, compare plans instead: which piece needed improving, which exchange was good for you, and where the weakness was. Different causes need different training, so do not call every loss carelessness.
Check the alternative
Go back one move and find two or three reasonable candidates. Try to explain each one without help, name your opponent’s best reply, and only then compare with the analysis. That order trains the act of choosing and shows why the attractive move turned out to be weaker.
Solve the position again
Hide the played move and the recommended one, give yourself a short time limit, and solve the position again. Afterwards write down a rule: for example, «check for loose pieces before attacking» or «activate the king first in an endgame». The rule has to be concrete enough to use at the board.
Collect the recurring theme
Save the position and come back to it in a few days. If a similar cause shows up in several games — a weak back rank, an overloaded piece, a missed in-between move — collect a small set of three to five positions. Such a set shows a stable habit and turns a review into a clear training plan.