I wonder if all these sacrifices were because of a lack of food. Better to give your kid to the gods than to watch them slowly starve to death during a bad winter.
"In especially uncertain times, such as when an emperor died, or when volcanoes erupted or severe earthquakes or famine struck, priests sacrificed captured warriors or specially raised, perfectly formed children to the gods."
related to the article above
https://www.theguardian.com/science/2013/aug/04/why-incas-pe...