There needs to be a way to move a boat other than forward momentum under sail. Example, you pull up to an island too close and a large sand bar extends out from the island, blocking you from moving forward without getting stuck on it. 1. Raise anchor and allow wind direction to blow the boat in the direction of the wind, so you can drift away from the island, with favorable winds. 2. Allow "spin in place" movement under low/no sails. Which brings me...