Every Church has Rosters. At the churches I’ve been a part of this usually means a spreadsheet document which is handed out at the start of each term which tells you who’s on what each week. Some church go-ers are excellent at writing these dates in their diary and then showing up dutifully when they are rostered on. If they can’t make it, they arrange a swap with someone else and then let the right person know. The problem is, not everyone is like this.