You should congratulate people on good news.
Harry is a manager and hears that one of his employees, Taylor, just got into graduate school.
Harry wants to decide how to treat the employee before they leave the team.
Harry tells Taylor that she's very happy for her and that he hopes she does well in grad school.
Harry starts to be less friendly towards Taylor and does not make any mention of her getting into grad school.
Taylor is appreciative of Harry's kindness and makes sure to let him know well in advance when she will have to leave the team.
Taylor finds Harry's behavior to be unpleasant and starts to bad mouth him to other employees behind his back.