However, even the slightest mistake makes things worse, and the game is soon over if you slip at all.
When you have a very good position, but not a won position, if you make a small mistake you will still have a very good position; just not quite as good as it would have been if you had played the best move.
The player with the inferior position needs to play more precisely than the player with the good position, but we are all human and we all make mistakes. Therefore the player with the superior position has the better chance to win.
This is why an advantage that is not enough of an advantage to force a win is still sufficient to produce a higher winning percentage.
This is a short section, but an important one. The inner meaning of "positional advantage" is right here on this page.
When you have a very good position, but not a won position, if you make a small mistake you will still have a very good position.
But if we can translate all these things into each other, what's in the next section?