Morale is more often than not the difference between winners and losers.
“That’s quite clear,” murmured the O’Keefe in my ear. “Weaken the morale—then smash. I’ve seen it happen a dozen times in Europe. While they’ve got their nerve there’s not a thing you can do; get their nerve—and not a thing can they do. And yet in both cases they’re the same men.”
It seems to me that bad morale has far more effect than good… you can believe in what you’re doing and still fail, but it’s vanishingly rare for someone with low morale to succeed. To do that you have to be a certain kind of bloody-minded, unstoppable curmudgeon, as inexorable as a glacier, which isn’t nearly as easy or as much fun as being a high-spirited and confident person.