It is rare for a business to care about something more than they care about time and cost.

Using McConnell's "Cone of Uncertainty" works well for me. I can't get sign off on "824 story points, and we can't tell you how long that will take or how much that will cost" but I can get sign off on "this will take between 4 and 7 weeks, and cost between $150k and $225k, and as we progress we can provide a more accurate estimate".

J.Ja