To a consequentialist, if your murder attempt failed, you're ethically fine (which is why many think consequentialism defies intuition and can't possibly be right).
To a deontologist, attempted murder is always bad (which is why deontology seems vague and misaligned with reality to some).
To a moral skeptic: see? The fact that we're going in circles means we're barking up the wrong tree with this whole ethics thing.