Yes, but the idea is you begin to know it is up or down on a given day. If I weigh a few days in a row (or every other day; just somewhat frequently) and the weights are something like 155, 156, 159, 156, 157 then I know my weight is around 156. A couple of weeks later they might be 153, 154, 157, 154, 155 and I am bouncing around 154 and have lost around 2 pounds. But what if I had weighed only every two weeks and I happened to weigh on the day I was 155 during that first stretch of days and 157 during that second stretch? That could be really discouraging.