Power
Every time a piece of software is installed someone gains and someone loses power. We need the cooperation of the losers, and we are in the middle.

Show stopper
What happens if you write the spec so someone loses. That is why the spec ends up wishy washy. At that point we blame the writer for being a bad writer.
We can't build wishy washy code so programmers have to deal with conflict resolution.

Vague specs identify conflicts.

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