One of the counter intuitive things you have to learn in sword play is letting your guard down. I mean literally, taking your sword off the defensive line, removing the cover that it gives you, in fact removing it completely from the space between your opponent and yourself.
This is hard to do because we like to protect ourselves from things that are scary/dangerous by building a barrier, a fence (as in de-fence) no less, with our arms or weapon(s) to keep the threat at bay. It's very natural and there is absolutely nothing wrong with it .... unless ... it's the more dangerous option ...
Here's the logic
If we accept that change creates opportunity, and that a holding pattern only gets more and more dangerous as the moments tick by, you can't stay there.
The reason it gets more dangerous is that when you do nothing, you are in fact waiting and you have no idea what is going to happen next, or when. So the temptation to take a risk grows, possibly because we have an innate understanding that waiting is bad, tactics go out of the window, and the fastest person tends to get the first hit .. though often eats one in return due to the risk they too are taking.
Neither party is controlling the space, the time, or the action, so bad things happen.
This is when you have 2 options - You use your opponent's fence as your bridge to close the distance and bring the live hand into play, or, if this does not work, drop your guard and invite the opponent to come to you (resulting in the same change in range).
And the range needs to change. Standing at static range on the center line is the most dangerous place to be.