The pacing of roleplaying sessions improves when the GM follows a simple principle: never ask for a roll if failure would lead to a dead end or other uninteresting result. This principle appears in various guises in GUMSHOE, HeroQuest, and the 4e Dungeon Master’s Guide 2.
Sometimes though, as in this recent discussion of what the DNDNext team might profitably nick from GUMSHOE, it becomes important to distinguish between an uninteresting result and a setback that makes the player unhappy.
Specifically, the so-called “whiff factor”, or prospect of rolling during combat and missing, is unrelated to the null result issue. Swinging and missing represents a loss for the player. In a mainline roleplaying game, the number of actions you can take in the course of a fight acts as an uber-resource. When you use them successfully, you whittle down your opponent’s supply of another resource, usually hit points. (Or free slots on a wound track, or whatever.) When you roll and miss an opponent, something has definitely happened—you’ve fallen behind, losing a chance to score.
Likewise, a shot on goal in a hockey game never leads to a null result. The player either scores, or has lost a chance to score, a resource the dynamic of the game works to restrict. In either case, the emotional crescendo becomes apparent in the stands. If the player scores, his team cheers. If he misses, the defending goalie’s team cheers.
Criticism may be leveled at a combat system where characters fail too often, dragging out the fight and undercutting the players’ sense of vicarious competence. But that’s a matter of striking a satisfying balance between success and failure, not of eliminating non-events.
A system may try to overcome its whiff factor by granting consolation prizes to players, in which they deal a lot of damage on a success and a smaller quantity on a failure. The question to ask here is whether that’s blunting the emotional rollercoaster of success and failure, or merely putting a new coat of paint on a skewed ratio between the two.