TagTime is a stochastic time-tracker; getting a needed ‘ping’ on an emergency day sure feels like a reward.
It also increases anxiety/focus if you’re skating the edge of your road, or prone to goofing off. Because you won’t know whether you’ll get a ‘ping’ before midnight, or whether it’ll come when your bladder demands a short break… (:
q.v. the discussion from Beeminiding productivity