The snake seems to be lazy as he wanted an easy way out to get his prey. The frog king gave him food for a long time without having the snake struggle for it. This made the snake decide to even eat the frog king who had provided for him all this while. The snake is also foolish since he readily believes the frog king when the king suggests he would go out of the well to fetch more frogs from wells and ponds nearby to feed the snake.