not do someone any favours idiom
（做某事对自己或他人）有不良后果；无助于
to do something that is likely to have a bad effect on you or on another person
You're not well, and you're not doing yourself any favours by taking on extra work. 你身体不好，加班对你没有好处。
[ by + -ing verb ] The government isn't doing the families of the victims any favours by hiding the truth about what really happened. 政府隐瞒了实事的真相，这么做对受害者家属没有好处。