When we embark on any new project, the unknowns exceed the knowns. What changes through the pathway are the kinds of unknowns and knowns we have to work with. These are unknowns and knowns relative to resources, expectations, strategies, influences, costs, risks, consequences and potentials.
Because of the ubiquity of change multiplied by our capacity for learning, creativity and agility, the number of our unknowns can ebb and flow without direct correlation to our knowns.
No amount or specificity of commitments we make about outcomes and timelines has the power to prevent the natural emergence and evolution of unknowns in a project. That's why in our Agile Canvas process, due dates indicate how long we are committed to working on specific desired outcomes, not our guaranteed prediction of when something is actually possible. We can work to any date, but we are always working with the unknown-known ratio tipped in favor of unknowns.
Why the vast majority of projects worldwide fail to deliver on time, on target and on budget is because the process is based on assumptions rather than questions. Only a question-based process has the greatest chance to succeed.