This is why you should never autoresolve a battle even when being outumbered

When speaking of single player campaigns, I saw some gamers autoresolving a battle that is theorically "lost" according to the autoresolve prediction. They surrender even before fighting. But in my opinion you should never surrender before even fighting. This is an example of a gamer who decided to manually fight a battle that according to the autoresolve prediction was "totally lost" but at the end he won. Watch from 6:03 to 15:00
https://www.youtube.com/watch?v=Ipxyn04PNXY