Liu Chan is the worst one. But why Liu Chan so lousy, because
his dad Liu Bei doesn't know how to teach him, he live in a
protected and pleasure environment since young, of coz don't know
much thing lah.
Liu Bei also one, when Guan Yu's province is under attack by Cao
Cao and Sun Quan, he refused to send reinforcement to help his
sworn in brother. The defeat of Guan Yu cause some other chaining
effect for example loss of land, the death of Zhang Fei, Liu Bei,
break up bettwen Shu and Wu.
Kong Ming also one, he purposely let Guan Yu guard the path to
watch for Cao Cao after the Che Bi battle. He think that if Cao Cao
is killed, Sun Quan will change target to Han Dynasty. wrong moves
lah.