I have that same question, going through my head a few times!!! BUT, dome of them are friends, sometimes life happens and they can't go online and do their daily to-do-lists. Give them time. I believe that they will come around and see all the benefits of SFI. Never give up, that is my motto. Just keep on encouraging them, don't force them or tell them they are not doing their share! They will then never become part of a great team. It is their choice!!!
