Math is scary, and often we stick to what we know because its easy, but the best games examine the mechanical choices they make, so I'm gonna demistify some shit about 2d6 math
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Alternate Title: PbtA designers, please stop using +/- x modifiers in your games.

Let's get into it. To cover the basics, *most* PbtA uses 2d6 dice resolution, with a 6- being a miss or fail, a 7-9 being a partial success, and a 10+ being a full success (with any 7+ refered to as a hit).

Since 2d6 averages to a 7, you default to a slightly higher chance of a hit than a miss.