Editing Unwritten: System Reference Document/Aspects and Fate Points (section)

===Double-Edged===

Players, good aspects offer a clear benefit to your character while also providing opportunities to complicate their lives or be used to their detriment. An aspect with a double-edge is going to come up in play more often than a mostly positive or negative one. You can use them frequently to be awesome, and you’ll be able to accept more compels and gain more fate points.

Try this as a litmus test—list two ways you might invoke the aspect, and two ways someone else could invoke it or you could get a compel from it. If the examples come easily to mind, great! If not, add more context to make that aspect work or put that idea to the side and come up with a new aspect.

GMs, this is just as true of your game and situation aspects. Any feature of a scene you call out should be something that either the PCs or their foes could use in a dramatic fashion. Your game aspects do present problems, but they also should present ways for the PCs to take advantage of the status quo.