The jury heard how Letby poisoned some of her infant victims by injecting them with insulin, while others were injected with air or force-fed milk.
Letby, 33, has been dubbed Britain's most prolific serial child killer of modern times.
Her callous acts have left the world asking, "What could have driven a nurse to kill?"
University of Newcastle criminologist Dr. Xanthe Mallett tells New Idea that these types of killers often have a God complex.
"In the Letby case there hasn't been a motive given but generally with killers like this there's a God complex: having the ultimate power over life and death," she says.
"There's a German nurse, Niels Hogel who killed 85 patients and sometimes he would resuscitate one after they had died to show off to his colleagues."
"A misguided altruism can also be motivation...they think that they're putting someone out of their misery."
Letby was arrested in 2018 when staff started growing suspicious of the unusually frequent infant deaths at the hospital.
Dr Mallett believes Letby's actions should have been questioned sooner. She says, people "were raising concerns which weren't followed up."
In a search of Letby's home following her arrest, police found paperwork and medical notes with references to the children involved in the case.
"I killed them on purpose because I'm not good enough to care for them," Letby wrote in one note to herself.
"I AM EVIL I DID THIS," said another.
Her search history revealed she'd repeatedly looked up parents of the deceased children on social media.
Judge James Goss said: "You acted in a way that was completely contrary to the normal human instincts of nurturing and caring for babies...the impact of your crimes has been immense."
Letby will never be freed.