Discuss and correct poor performance. Volunteers especially want to do things correctly, and they usually welcome opinion. Take action as soon as problems start to develop. When all else fails, reassign or terminate the volunteer. Guard against unproductive work.
Unproductive work requires correction, which is a waste of the agency's time and money.
Use a paid staffer for basic program management, coordination and support. Few volunteers are willing to do the odious job of paperwork, reports and plans. These are not necessarily reasons to treat volunteers differently, however. In fact, because volunteers are not bound by a paycheck to the job, good supervision is even more important. Treat volunteers as equal, valued members of the staff.