Why gargoyles are on churches why?

A gargoyle is a carved stone grotesque designed to carry water away from a roof and the walls of a building, most obviously seen in churches. It is most often seen as a medieval addition, but was known to the ancient Greeks , ancient Egyptians and derives from the Latin Word Gula. Throughout the history of churches, gargoyles were used to convey the idea of evil, convincing people to go to church with the idea that the end was near. Gargoyles can represent Lions, the Wolf, Snakes. Goats, Monkeys, Eagles, Griffins, Harpies and Mermaids. They would now be replaced by gutters

It was believed in the 19th century that gargoyles warded of evil and served as protection against witches.

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