I am not sure but my guess is that it is just a way to keep track of the guys you have scouted. So say for example you have scouted 10 guys and you put them all on the watch list and 8 of them have now been picked by the time you get to your pick. Now in stead of having to going threw the list of players to find the 2 left you have scouted you can just look at the watch list.