Task requests come from a "dice roll" (random number generator) that happens every hour. "probability 0.25" means that every hour, there's a 25% chance that the die roll will result in a new janitor request, if one hasn't been queued up already. And "businesshours #false" means that the dice will get rolled 24h/day, instead of just during the hours when the business is actually open.

I would recommend switching to "probability 0.1 businesshoursonly #true" to drastically reduce the number of requests.