Most of Shakespeare's tragic heroes have some kind of tragic flaw, including Hamlet's hesitant nature and Romeo and Juliet's impatience, along with the protagonists of many classical tragedies, such as Oedipus and his need to discover the truth, which turns out to be that he killed his father and married his own mother. A tragic flaw, or "hamartia" to the ancient Greeks, is any attribute of a main character's personality that results in their own destruction. As in the examples above, this attribute may compel the main character into either self-destructive action or self-destructive inaction.
Tragic flaws are often the subject of debate by literary scholars. Those of timeless characters like Hamlet and Oedipus, for instance, have long been subject to interpretation.
For classical writers like Aristotle, tragedy had a somewhat more rigid definition that may have rejected Macbeth as a tragic hero on the grounds that his ambition made him evil and he therefore deserved his unpleasant fate. However, accepting him as a tragic hero, his tragic flaw would be that ambition.
In the moralistic tragedies of the middle ages, such as from Chaucer and Bacaccio, tragic heroes were often men of good standing who somehow fell from grace. In line with the Christian sensibilities of the time, their tragic flaws were often portrayed as sin.