Macbeth is charged to not fail the feast by Lady Macbeth. This is ironic because, despite her admonition, Macbeth does indeed fail to keep the feast when he sees the ghost of Banquo, revealing his guilt and inward turmoil to all the guests. This contrasts with Lady Macbeth's efforts to maintain an appearance of normalcy and control.
In both cases, the ghost that appears in Macbeth is summoned by the guilt and inner turmoil of Macbeth himself. The ghost of Banquo is a manifestation of Macbeth's guilt over his role in Banquo's murder, while the ghost of Lady Macbeth represents his guilt over her death and his descent into madness.
Banquo's ghost. But let's be fair; Macbeth told him to "fail not our feast", and Banquo didn't, even though he was dead.
Lady Macbeth tells Macbeth that if they fail in their plan to murder King Duncan, they will simply try again until they succeed. She reassures him that their ambition and determination will ensure their success.
Unfortunate. Ironic.
The two murderers in Macbeth succeed in carrying out the murder of Banquo, as ordered by Macbeth. However, they fail in killing Fleance, Banquo's son, who manages to escape.
It's difficult to say. One possibility is that the ghost was fulfilling Banquo's promise to "fail not the feast" and so he sits in the only available place. Or possibly, he wants to sit in the place which will be sure to get Macbeth's attention. Or he is trying to twist Macbeth's tail by reminding him of the witches' prophecy by sitting in the king's seat, except that the prophecy said his children would be kings not him.
It depends on whether you think the ghost is real or not. If it is real, it is not about Macbeth's mind, but about Banquo's spirit seeking justice, or alternatively keeping his promise to "fail not our feast". But if you think that the ghost is imaginary, a false creation of Macbeth's heat-oppressed brain, then it tends to show the guilt which is eating away at his sanity, and prompting him to become obsessive about his safety.
Lady Macbeth, in Act 1, scene 7.
The two murderers succeed in carrying out Macbeth's plan to kill Banquo. However, they fail in killing Fleance, Banquo's son, who manages to escape.
He is confident that he will not loose the kingdom to malcolm because the witches have said that he won't be defeated until the wood's move towards him and he can't be killed by anyone except a man not born of woman. (Macduff).
I would drive it at least enough to keep the battery charged. The battery can actually fail just from not being charged.
Lady Macbeth convinces Macbeth to commit the murder by questioning his masculinity and courage, telling him that he is not a true man if he does not follow through with the plan. She also assures him that they will not fail and promises to take care of all the details of the murder. Additionally, she plays on his ambition and desire for power, suggesting that by committing the murder, they will be able to fulfill their ambitions and secure their future.