This is an important lesson for parents. God often doesn't answer our prayers right away to test us, humble us, chastise us, and teach us. God didn't just give food and water to the Jews. God waited until they were thirsty to the point of dehydration. God withheld food until they felt that they were starving. God tested them, to see how they'd react when the going got tough. Instead of trusting and thanking God, they complained and rebelled. They failed the tests God gave them. So God had to chastise them repeatedly. This is exactly the way God operates still today. People get angry and rebel against God because God makes them wait, forces them to trust Him, and doesn't spoil them. There is much to be learned from all this as parents.