It is quite obvious to anyone familiar with Christian scriptures, and the ethics that came from them, iI think? He claims that the ends/result are what makes it moral or immoral, justified or not.
That means that I can try to kill you, but the morality of it changes depending on how good I am at trying to kill you. I can smash your head, trying to kill you, but if I'm too weak and nothing really all that bad happens, it was a moral act. Conversely, justifying by result, if I'm tossing stones over a wall at the dump, not knowing you're there, and accidentally kill you, results-oriented justification says that I am more morally culpable than the weak person who attempted murder.
(We'll forgo a discussion for now on the moral ramifications of negligence in the second example. It sufficed to show the differences between the two moral outlooks.)