For myself and many others, writing-for-a-living places great importance on getting it right. Doing any kind of research, engineering, technical writing, even rules writing for a game requires long stretches of tedium. Fact-checking, revising, setting down the details, these all need careful work.From this activity we learn how to react to boredom as technical writers: Persevere!
Writing creative material, on the other hand, needs a different reaction to boredom. If you are bored writing something, or dreading the task because it is dull; that is your signal to cut that piece of writing out. If you are having fun writing something, then there's a chance - only a chance - that the person reading it will enjoy it. But bored writing is dead writing.
This explains why I can do creative work at times when technical writing eludes me, while other times I need to deaden my mind with drudgery and word-crunching. They are two different resources, two different skill sets. There is no virtue in writing boring creative prose!
Consider: I am describing the wizard's tower of a castle. The tedium of describing five or six small rooms, each stacked on top of each other, weighs on me. To escape this, I decree that the tower's interior is mostly taken up by a misty extradimensional space, threaded by a winding stair; I describe that and the wizard's chamber at the top, and state that a number of other rooms and storages exist in the mist but are not accessible to anyone but the wizard. Need I feel guilty, lazy? On the contrary, I have done something new and added interest to the adventure.
Consider: I am describing the rooms of a group of NPCs in that castle. To escape the tedium of describing the furnishings of each one I simply say "rooms 21-26 are furnished in the usual manner of bedrooms" and presume that any game master of 6 years or older knows what that means. This leaves me the room and motivation to put in the interesting stuff - goods to loot, things to interact with if invited back there.
As anyone who has ever sped up the action, thrown out a rule, or handwaved a procedure will recognize, the rule of boredom applies to game-mastering, too. Boredom occurs when players are neither engaged in adventure, anticipating adventure, or savoring the last adventure. All quiet moments in the game should be strongly focused on one or both or the last two of these.