Final answer:
Bob Ewell's attack on Atticus's children was driven by his need for revenge against Atticus for humiliating him in court, not by jealousy or being paid by someone else. His excessive drinking may have influenced his behavior, but the primary motivator was revenge.
Step-by-step explanation:
The reason behind Bob Ewell's attack on Atticus's children in To Kill a Mockingbird is motivated by his desire for revenge on Atticus. Bob Ewell felt publicly humiliated by Atticus during the trial of Tom Robinson, where Atticus defended Robinson and in doing so, exposed Ewell's lies and his family's squalor. This caused Ewell to harbor a deep resentment and seek retribution. His decision to harm Atticus's children instead of confronting Atticus directly is an act of cowardice. Moreover, Scout's observation of the smell of stale whiskey suggests that Ewell's judgment and inhibitions were likely impaired due to his excessive drinking, but alcohol was not the primary cause of his actions. It was his malign intent towards Atticus that drove him to commit the attack, not jealousy, not being paid by someone else, and while influenced by alcohol, it only augmented his pre-existing malice.