Answer and Explanation:
1. The monster kills to take revenge on its creator. That's because he was rejected by Victor, which caused him a lot of pain and suffering, as revenge, he decided to cause pain and suffering for those who abandoned him, leaving him as lonely as he was.
2. The monster shows that all this would be avoided, if he had received a little affection, understanding and suppression of his emotional needs, but all this was denied to him by futile motives such as his appearance.
3. This represents a burden for us, as readers, because it makes us recognize ourselves both in the showroom, in need of attention and vindictive, and in Victor who is afraid of his creation and rules it because he is not beautiful.