Compassion - Miriam-Webster "sympathetic consciousness of others' distress together with a desire to alleviate it"

Will this make a person soft, weak? Many can see how this is a good trait with loved ones or the unfortunate in our society but on a daily basis - will a person get taken advantage of at work? in fighting for justice? or dealing with the more fortunate in society at large? How does this central tenant of Buddhism apply in a person's everyday life?