Don't find fault. Find a remedy. The point should not be to keep score of these errors, but to find practical solutions to problems. Skilled case students advance the discussion by building on the comments of others. Through the process of building, we arrive at solutions.
Honest differences are often a healthy sign of progress.
The evidence is that a group of decision-makers who think differently make better decisions than a group who think alike. The only difficulty is that decision-making among people who don't think alike takes more effort. In striving for managerial excellence, we must cultivate patience with which to endure the unexpected twists in a decision-making process among a diverse group of people. Excellence is to do a common thing in an uncommon way. These three quotations offer sensible guidelines.