Bob Briner's Leadership Lessons of Jesus has a fascinating example on why it is very difficult to maintain focus on our projects and goals :
Consider a Sunday school class formed with a very simple mission: to study God's Word. One hour a week is set aside for the sole purpose of Bible study by a homogeneous group. There is a simple mission with a very sharp focus. Yet here is what often happens. Someone says it would be nice to open the class with a song or two. Fine. The class begins with singing.A suggestion is then made that the class should promote fellowship among its members. Fine. Time is set aside at the beginning of the class for coffee and fellowship. Class time is taken to discuss and plan for fellowship opportunities outside of class. (“Should we have a potluck or a picnic? How does two weeks from Friday fit into everyone's schedule? How about three weeks from Friday?”)The church leaders recognize that many who come to Sunday school do not stay for the worship service so they see class time as perfect to make general announcements. Time is set aside for this. Furthermore, since the Bible admonishes us toward good works, the class decides it should support a charitable endeavour Which one? How much should be given? When can someone bring a report on how our money is being used?You get the idea. The focus on Bible study, the real purpose of the class, has been lost. Bible study is, at best, relegated to a lesser role, and the goal of a discipled class has been dissipated.
Once the focus is lost it is very difficult to get it back. Maintaining focus becomes very costly and painful. In the example, it won't be easy for that Sunday school class to regain its original vision—especially when those other worthy goals have been added. The human tendency is always to drift away from our original commitments. And when we sense this happening, the cost of moving against the tide will be enormous. Bob Briner, alluding to the Lord Jesus's statement in Mark 9:45 says trying to get us back on track is "like cutting off a hand or plucking out an eye".