From Longman Dictionary of Contemporary Englishit’s no good (doing something)it’s no good (doing something)used to say that an action will not achieve what it is intended to achieve It’s no good telling him – he won’t listen. → good
Examples from the Corpus
it’s no good (doing something)• It's no good just bleating on about the rising tide of crime to get money out of the government.• It's no good pretending you've any aptitude for art when it's quite clear you've none at all.• It's no good printing my letter if you're just going to do it again.• It's no good tying up money for years unless you're certain you won't need it.• It's no good, she rebuked herself sternly; there's no future in feeling like this about Luke Travis.• Here we are on the hills, and it's no better.• But ... but I will worry if I think you are hanging on waiting, because it's no good.• It's very easy to tell an actor that it's no good. 