Majoc:
Sometimes scientists change their minds. New developments cause a rethink. If this bothers you, consider how much damage is being done to the world by people for whom new developments do not cause a rethink.
    -- Pratchett, Stewart and Cohen: The Science of Discworld, 2nd edition

I think this is provoked not so much by the change of mind itself, as by the rapidity of the change.
In under two years the government have brought in at least 10 policies which have later been fully or partially reversed. This doesn't seem to be because new information has come to light, but because the policies (and their effects, or expected popularity) weren't fully thought through before bringing them in.