I think both success and failure are important when you are raising children.
Success is important because it encourages children to do something better.
It teaches them how they can avoid failure, and once they have had success, they will want to experience success again. But even though success can teach children, we must remember that in their early years they learn through their own failures. For example, when children start to walk, they always fail many times before they finally can walk by themselves. Their parents just encourage them to do it, but they can't do it for them. Everybody remembers both their successes and their mistakes, but I think that you remember more when you cry than when you smile.