Because you're a normal human being, and such deplorable actions are way beyond your comprehension and that of most of the population.
Murdering seven children, who are in your care and who you've sworn an oath to protect, is not the actions of the absolute majority of people.
Therefore, most people will find it hard to understand, and rightly so.
@davek there were deliberations on the attempted murder of other children.
She will definitely appeal, there is no reason for her not to, but being cleared of any of these convictions is unlikely, let alone all of them. She'll die in prison.