Delegation is more than just assigning tasks to people. For delegation to be successful it has to be done while taking into consideration a person's unique spiritual giftedness and passion. For instance, no pastor would want to ask me to become a choir director. My musical abilities are extremely limited, and I am being kind to myself. I have a great voice in case of fire or shipwreck, but you don't want me to lead singing. In a similar fashion you would not want to ask the church grouch to lead the church greeter team. One of the most important things a new pastor can do is to identify the gifts and passions of the people in the church so when it comes times to ask people to do certain things the pastor will know who is the best person for each task.
There are several good reasons why we need to do a better job at delegation. One is that it provides our church with more ministry points. If the pastor is the only minister in the congregation then the ministry of that church is limited to one person. But, if the ministry has been delegated to a number of people the church has just multiplied its ministry by that number. Second, it helps prevent fatigue for the minister. Involving many people in the ministry of the church reduces the burden the pastor must carry. Thirdly, it helps with disciple-making.
Growing disciples is more than just offering a number of Bible studies in the church. Disciples need to learn the Scriptures, but in order for them to become disciples they must have opportunities to put into practice what they are learning. Discipleship is education + service. Delegating ministry opportunities to others enables them to grow as disciples. Refusing to delegate stunts that growth.
If our churches are to be serious about developing disciples we must learn to delegate. If we are serious about wanting to grow our churches we must learn to delegate. If we who are in the ministry want to enjoy more productive ministries while maintaining a measure of balance in our lives we must learn to delegate.