We think about planning as a process of identifying, organizing and working on our most important questions. It's in direct contrast to the old model of identifying, organizing and working on our most important assumptions.
Questions cause us to be more curious, open minded, creative and open to learning. Statements keep us more presumptive, cautious and learning disabled. Questions result in more alignment; statements result in more argument.
Statements create the illusion of uncertainty because we don't give full and actionable attention to all of our questions. Ultimately, even the most confidently or anxiously declared statements actually create less clarity and more risks than questions.