Very good advice. The problem with most people is that they don't know their core values, and some don't even care, as long as they are living life the way they want. Another thing about core values is that it's prone to change when a person goes through a very difficult or traumatizing event. A very upright person will suddenly become wayward because of the challenges life throws at them, and although some people might be able to retain their core values despite the challenges, not everyone is that strong to do so
That's why it's necessary to teach the children core values and it's become part of them and they know their core values like they know their name. This will help it to stick with them during stormy days.