He divvies up the categories of when to roll into three categories:
Challenge, Excitement and Drama.
A few days ago, gaming with Storn asked to make a roll to do something and I told him not to bother. “I can’t think of any interesting outcomes that come from you failing the dice roll.”
Its the old, Say “Yes,” or roll the dice Maxim. When to say, “Yes,”?
One good and easy criteria is when failure just is not interesting.
What is interesting?
A set-back, an injury, a change in a social balance, a drive towards conflict, a mounting of tension, a loss of a resource, a scar, a threat to something the player cares about.
Roll the dice when failure is interesting and adds something to the game.
Otherwise, keep on keepin’ on and keep those dice in your bag.