I think that when you find a relationship with Jesus, the effect that it has on your person is something that you are excited to share.
The Bible tells us to be let our light shine and to be not under a basket but to be on a hill.
In the beginning this meant that everyone would need to be told this good news as it was then VERY new. Today, nearly everyone is familiar with Christ's teaching. Therefore, rather than being a preachy message we are to reflect God's love for us in the way that we treat others. To reflect what we have received. To be illuminators in a dark world.
This occurs best in relationships and not through door to door preaching. It means extending ourselves to others; reflecting God's love so that others are drawn to God by wanting the love and grace we have received and the changes that it has made in our personal lives.
Very few people respond to being preached at at the door. I am interested in talking to jw's at my door and yet when one came I wasn't interested in talking and just wanted him to leave.