I would assume the expectation came about after WW2 where losing meant devastating ramifications for the losing party.
On the other hand in a situation where warfare is considered with less weight and investment feels like it’ll embolden states to return to a state of frequent warfare.
One mechanism that wasn't described in the article and for fairness I know little about when it comes to prehistoric hominids is the role of community splits forcing certain members to go out or die trying to establish hegemony.
If you right click and go to the open with menu and scroll to other, there's a checkbox with the finder window called "Always Open With". This way you don't need to remember which button to hold down.
On the other hand in a situation where warfare is considered with less weight and investment feels like it’ll embolden states to return to a state of frequent warfare.