Yeah, PbtA is an interesting case. On the one hand it seems to cover everything because, by definition, anything that might possibly happen fits into one of the buckets. On the other hand, the rules don't really tell you what to do because, for an awful lot of those cases, they don't really tell you the outcome. Ok, so I either put the player "in a tight spot" or she "loses something of value". Now I have to invent what that means. So I'm really just improvising the outcome after all.
And if the player is the sort that wants to rules to define everything, so that the DM doesn't have too much power, there's a decent chance when I say, "Ok, you succeed, but you lose your grandmother's locket that you've had since you created the character" she is not going to like it.