not do (someone or oneself) any favors(redirected from not do themselves any favours)
not do (someone or oneself) any favors
To be problematic or detrimental to someone or oneself. A noun, pronoun, or reflexive pronoun can be used between "do" and "any." I knew that I had to get up at 4 AM today, and I didn't do myself any favors by staying up late last night.
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.