Maybe some posess the skill to effectively and consistently take running deer. I'm definately not one of them. If I were to shoot at a running deer I would be relying on luck to make a killing shot. Out of respect for the deer I'm just not willing to take such a high risk for wounding. Obviously I can't gaurantee even with a standing shot that something might go wrong but at least if the deer is standing or maybe slowly walking and it is within a range I'm comforatble with, then the chances of a wound are pretty small.