A message crafted with an “against” in mind is reactive , is about vilifying , demonizing or rejecting.This thus more often than not would convey a demotivating negative message.
As against this a message crafted with a “for” in mind is about feeling inspired , ignites the hunan spirit and makes us feel optimistic and hopeful thus inspires us.
Hence an impactful vision statement in otder to inspire a group should have a “for” rather than an “against”.
Simon Sinek mentions this in “The Infinite Game”.