Beat a dead horse.
Beat a dead horse.
Beat a dead horse" paints a graphic picture of uselessness and wasted effort. The vivid imagery of this idiom suggests that continuing to pursue or discuss an issue that is already resolved or hopeless is as futile as attempting to revive a deceased horse through beating. It is often employed in discussions where one party continues to harp on a point that everyone else agrees is settled or irrelevant. In a meeting, someone might say, "Let's move on and not beat a dead horse.
There's no point in begging; you're just beating a dead horse.
No amount of begging will change the situation, so it's a waste of effort to keep trying.
Why keep arguing? You know you're beating a dead horse.
Continuing to argue is pointless because the matter is already decided.
Continuing this discussion is like beating a dead horse; we've made our decision.
Trying to discuss this further is futile because the decision has already been made.