Because of lack of moral principle, human life becomes worthless. Moral principle, truthfulness, is a key factor. If we lose that, then there is no future.
Who gave thee, O Beauty,
The keys of this breast,--
Too credulous lover
Of blest and unblest?
Say, when in lapsed ages
Thee knew I of old?
Or what was the service
For which I was sold?
It helps remove whatever fears or insecurities we may have and gives us the strength to cope with any obstacles we encounter. It is the principal source of success in life. Since we are not solely material creatures, it is a mistake to place all our hopes for happiness on external development alone. The key is to develop inner peace.