I believe the Lord keeps some people from returning to our church because he wants to make sure that His ministers will keep first thing first: to love and care for the existing flock. A common temptation and error that many church planters and revitalizers make during their ministry are that they are often consumed with a desire for growth that they mistakenly end up neglecting the existing members of the church. It is important for all ministers to recognize that we are first and foremost given to the flock which Christ has entrusted to us. Evangelism is important. Church growth is important. Strategizing to draw more people into the church is important. Nonetheless, the most important command which Christ has given to all ministers is to feed His sheep under our care (John 21:21).