Up, down, or sideways, GIGO works in all directions, even with non-managers. World views that differ from the information source tend to add garbage into the information stream.

I suppose it's just most noticable since managers' world views tend to differ radically from most sane people (e.g. distrust bad results; go non-linear if it really turns out to be bad). Where I work I see a lot of distempered stuff come down from high above, which I suppose had some rational intent at the beginning. Lukily, by the time it gets to my level it is so badly distorted there is nothing left to implement...