When I was working at a big online travel site, we used to have a requirements document template which started with a "flexibility matrix". It was a two-by-two

When I was working at a big online travel site, we used to have a requirements document template which started with a "flexibility matrix". It was a two-by-two grid with "scope" and "date" along the y-axis and "most flexible" and "least flexible" along the x-axis. The stakeholders were supposed to indicate to us whether the scope or the date was "flexible". Of course, we got an unending series of requirements where the date was "least flexible" and the scope was "most flexible", never ever ever the other way around. It got to the point of such ridiculousness that we finally started trying to flex the scope because the dates were so unrealistic. Management's response? Add another row and column in the matrix of "resources" (that is, it's ok to add people if you need to) and "somewhat flexible". So after that all of our requirements were "date least flexible", "scope somewhat flexible" and "resources most flexible".