The knowledge of this friction is a chief part of that so often talked of, experience in War, which is required in a good General.

Certainly he is not the best General in whose mind it assumes the greatest dimensions, who is the most over-awed by it (this includes that class of over-anxious Generals, of whom there are so many amongst the experienced); but a General must be aware of it that he may overcome it, where that is possible, and that he may not expect a degree of precision in results which is impossible on account of this very friction.

Besides, it can never be learnt theoretically; and if it could, there would still be wanting that experience of judgment which is called tact, and which is always more necessary in a field full of innumerable small and diversified objects than in great and decisive cases, when one's own judgment may be aided by consultation with others.
Just as the man of the world, through tact of judgment which has become habit, speaks, acts, and moves only as suits the occasion, so the officer experienced in War will always, in great and small matters, at every pulsation of War as we may say, decide and determine suitably to the occasion.

Through this experience and practice the idea comes to his mind of itself that so and so will not suit.

And thus he will not easily place himself in a position by which he is compromised, which, if it often occurs in War, shakes all the foundations of confidence and becomes extremely dangerous.
It is therefore this friction, or what is so termed here, which makes that which appears easy in War difficult in reality.