Michael Wilkinson, the founder of Leadership Strategies, makes what might appear to you as an outrageous claim. From their facilitation work with hundreds of organizations, he concludes that people disagree in a meeting for only three reasons.
Level 1: They do not hear each other
They have not clearly heard and understood the other’s information/alternative and reasons for supporting the information/alternative.
2. Level 2: They have different values or have had different experiences
They have heard and understood one another, but they have had different experiences or hold different values that result in preferring one alternative over the other.
3. Level 3: Outside factors
The disagreement is based on personality, history with one another, or other factors that have nothing to do with the alternatives.
This model is particularly useful because facilitators can be more successful in serving their groups if they understand the three reasons people disagree. They should learn methods for detecting which reason it is and have tools and techniques for addressing each of the reasons.
My 2 cents would be to factor in the concept of “Weltanschauung” (worldviews) which I use in my consulting practice. In my experience, people disagree because they have different worldviews about the perception of a given situation. Nothing else. A different worldview works like a lens and all facts get distorted to fit the fundamental beliefs that lie behind. Sometimes worldviews are so strong, they not only contaminate the perception of facts (level 1 reason for disagreement) but they can become attached to broader outside factors (level 3 reason for disagreement).