The job of a campaign manager is often considered unpleasant; it's their responsibility to encourage voters to vote for the candidate they represent. Some people enjoy the role, if they like the person they're working for. Being forced to make endorsements for someone you dislike isn't an enjoyable experience. If the manager doesn't like their candidate, they're much more uninspired to promote their boss; the likelihood of this increases if the candidate is ungrateful for their manager. Still, the manager must enrich the story, enlarging images of their hated boss and writing catchy slogans that aggrandize their politician. I give campaign managers a lot of credit.