On a literal level, Macbeth suffers the consequence of death for his actions. He is beheaded in battle by Macduff, whose wife and children had been slaughtered by Macbeth.
On another level, Macbeth suffers losing everything he valued in life before he loses his life itself. Although he believes that murdering his way to the throne will bring him happiness and fulfillment, he finds that the opposite is true. Because of the way he achieves the throne, he lives in constant fear and suspicion of the people around him. He becomes isolated, unable even to confide in his once beloved wife. Achieving his ambition does not bring him the joy he had dreamed of, and this reality makes him increasingly bitter. He begins, for example, to deeply resent his former close friend, Banquo, as well as to become suspicious of him for knowing too much about the witches' prophecies. He has this friend killed and attempts to have Banquo's son killed as well.
Macbeth has all the dissatisfactions that come with being incompetent in a job. Rather than a beloved ruler, he turns into a hated and feared tyrant, who so mismanages his rule that Scotland enters into a civil war between himself and Malcolm, the rightful heir to the throne.
Macbeth grows dead inside. He loses his moral compass to the point he orders Macduff's wife and children killed. He is so distant from his own wife that he has to be told she is sleeping walking and going mad. When she commits suicide, he can hardly feel any emotion at all. In his final soliloquy he expresses what a misery life has become to him, saying:
Tomorrow, and tomorrow, and tomorrow,
Creeps in this petty pace from day to day,
To the last syllable of recorded time;
And all our yesterdays have lighted fools
The way to dusty death. Out, out, brief candle!
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,
Life has become a chore he wishes were over. He experiences no joy, no connection, and no meaning. Ironically, achieving his dream his made his life empty to him.
As an added twist, he is robbed even of the security that comes from the final prophecies he demands of the witches. They trick him with clever wordplay, giving him false assurances. For example, they tell him no man born of woman can kill him. It is only after he finds out that Macduff was born by a Caesarian section that he realizes that even the witches have turned on him.
Macbeth is punished with death, but everything that gives a normal human life meaning—friendship, love, trust, a conscience, a sense of connection, feelings, and hope—had died already.