Victor initially wants to experience the glory of creating life. He works obsessively for years on the project of animating dead body parts. This experience has a negative impact on his health and isolates him from other people. It is not physically or mentally healthy for him to be so single-mindedly obsessed with this goal.
When he achieves his goal, it also negatively impacts him. Like many people who pursue a dream, achieving it is not all he expected, but in Victor's case, it goes beyond the dream merely not living up to his ideals. He is, in fact, utterly repulsed and distraught over his creation. As soon as it is alive, he rejects it, not accepting any responsibility towards it as its creator. He looks only at the hideous outward form of the creature, and he judges it solely by that, not waiting to see that the creature has a caring soul that yearns for love, acceptance, and companionship.
Victor also experiences revulsion when he creates a companion for the creature, so much so that he destroys the female companion.
When the creature kills Victor's loved ones out of despair, grief, and revenge, Victor suffers greatly. He decides he must destroy his creation and chases it obsessively. This too has a negative impact on him.
These negative experiences, which derive largely from Victor's inability to empathize with his creature, or see the world from its point of view, remain largely unresolved throughout the novel. Frankenstein simply can't take responsibility for his obligation to "parent" the creature he has created, and this, in turn, creates an endless run of problems. In his pride, Victor creates life—but has no capacity to nurture it. The novel is a cautionary tale, warning against trying to "play God."