Victor's motives, initially, were to create life; to have dominion over death. He was inspired to this by the death of his fiance. But, even before her death he was intrigued and curious about the human body and what animated it. Doctors were forbidden to do such experiments, but he broke with convention and practiced in secret. Later, his motives become one of making amends. He wants to distroy the creature he has made because it has turned out so wrongly. Whether it is an ego trip to erase his mistakes, or his motives are to take a dangerous individual out of the population, we can only speculate. But, his final motives are to destroy the creature at all costs.
