What is victory? Is it to defeat your enemy on the field of battle? Is it to simply repulse his armies and slay his misguided warriors? No, this is only the very beginning!

True victory is to crush your foes utterly, to shatter his armoured legions and run down his fleeing troops as they scatter. Pursue them to their lairs and burn them out. Burst into his unholy temples, smash down his icons and topple his foul idols. Burn his heretical works and leave no stone upon stone. Slaughter his followers, their families and their livestock lest any of their taint remain. And when that is done, put the ruins to the torch.

Any that have dealt with them or given them succour must be obliterated, for memory is insidious and though you have crushed their will and their bodies they may yet return. Send warrior scribes to excise the records of their name, expunge their deeds from the annals of history and remove even the memory of your foe's existence. Only then have you truly won.

WH 40K