Many critics hold Lady Macbeth responsible for Macbeth's downfall and destruction, citing her ambition, which seems at times to be deeper than her husband's. Much is also made of her coldness and deliberate manipulation of Macbeth when he wavers in his intent to kill King Duncan and assume power. However, the drama is named The Tragedy of Macbeth, and Macbeth is one of Shakespeare's tragic heroes, a once good man who is destroyed by a fatal flaw within himself. A stronger argument can be made that Macbeth alone is responsible for his destruction, since it is his personal ambition that makes him vulnerable to his wife's demands, as well as to the deceitful prophecies of the witches.
As he is introduced in the play, Macbeth is a brave general, battle tested; he holds a respected position in Scotland and enjoys King Duncan's favor; he has wealth and power of his own. He did not achieve his status by being a weak and malleable man. It is only when his ambition, the fatal flaw in his character, is engaged that Macbeth makes the choices that lead directly to his destruction. He chooses to embrace evil. Were it not for that fatal flaw, Macbeth would not have been seduced by the witches and influenced by Lady Macbeth.