In Shakespeare's Macbeth, the tragic protagonist's ambition and hubris (acting above his station in life) cause Macbeth to inflict harm on others. That harm is the direct result of Macbeth's flaws.
Macbeth's ambition to be king of Scotland, and, later, to leave the thrown to his heirs, leads him to assassinate Duncan, kill Banquo, and order the killing of Fleance. As if these murders aren't bad enough, he also orders the slaughter of Macduff's family, a move which has no political or strategical value.
Macbeth's flaws contribute to his transformation from loyal thane and general to usurper of the throne to murdering tyrant. All of the suffering that results is directly linked to his tragic flaw. Macbeth, a noble, as Elizabethan tragedy requires, acts ignobly, and great suffering, as well as much blood, unnatural occurences, distrust, equivocation, and manipulation result.
As the violence and murders begin to pile up in the play, Macbeth becomes more and more immune to suffering, until, by the end of the play, his very famous "Tomorrow and tomorrow and tomorrow" speech reveals that life has lost all meaning for him. Al the suffering of the play has brought him to the tragic place of immunity to feeling or caring about life or death -- including the death of his wife.
In the early scenes of the play, Macbeth is not at all convinced that he should step into the realm of betrayal and murder by killing Duncan. Lady Macbeth plays a huge part in convincing him to take his opportunity for greatness by murdering Duncan so that he can become king.
Once Macbeth, crosses the line and commits murder by betraying the man to whom he has sworn loyalty, there is no turning back. He murders his good friend Banquo (and tries to murder his son) and takes out Macduff's wife and son. The carnage, once it is unleashed, has no stopping point and the tragic events of the play are further developed as these gruesome events begin to strip life of its meaning for Macbeth.
In Act V, scene v, he says that
Life's but a walking shadow, a poor player
That struts and frets his hour upon the stage
And then is heard no more. It is a tale
Told by an idiot, full of sound and fury
In this speech, Macbeth reveals the real tragedy for him of his actions. Life is a farce to him now, full of lots of noise and angst and action, but for all of this, it means nothing.