The decrease in the number of warehouses means that more people leave the scene.

Leaving is closing the position.

Closing a position requires someone to accept it from you.

Either someone leaves or someone enters, no.

For example, I have an empty order of 1 lot, which means that my position is 1 lot, and you have an empty order of 1 lot, which means that your position is 1 lot, and the total positions of our two positions are positive. However, if I buy and close, and you sell, there will be no position for both of us, then both of us will leave and the position will be reduced.

You took mine, I took yours, but we all left, okay?