I think, when you are totally satisfied from your life and from what you did and still doing in your life accounts for a person's success.
When you become a motivation for someone, when you are able to make someone's life better in some ways, when you become the reason of someone's smile, when you achieve your highest career goal through your hardwork, perseverance,dedication and punctuality.when you are at a position to bring positive changes to someone or within others.....
All this together constitute a way of or a position of 'SUCCESS' for me.