How does SnapOn = 1 work?

Discussion created by Lady_Jane on Jan 7, 2011
Latest reply on Jan 21, 2015 by curtvprice
I have delineated just over 7000 catchments (batch watershed delineation) with SnapOn set to 1.  For all except roughly 5, the watershed point produced is snapped to the center of the flow direction grid cell in which the original batch point falls.
For the other ones, the watershed point has been snapped to another cell 5 or 6 cells over.  This has resulted in my watershed being delineated to the main stream, and not to the tributary I am interested in.
Does anyone know how the SnapOn feature actually works, and why only 5 of my 7000 points would be moved?