When we come together in any kind of collaboration or meeting, we usually have no shortage of opinions. Some of these are facts and some are assumptions. In the Agile Canvas process, we get every assumption translated into at least one new question. Where untested assumptions create the risk of our getting stuck and lost, new questions keep us focused and realistic.
What we resist letting the group waste time getting bogged down discussing and debating opinions as assumptions, especially where their expression disguises them as facts. Every minute of this postpones learning and action.
Some groups and their leaders allow and even encourage discussing and debating opinions precisely because their unspoken agenda is to avoid learning and action, defining success as the lack of failure.