Sometimes in this activity a participant will short circuit. He will cling to the notion that the challenge is impossible. Even as other teams around him triumphantly announce success, he will continue to pronounce this an unsolvable task doomed to failure. Over and over, he will repeat his conviction.
From experience, I know his team will fail. They always do. One vocal naysayer will smash any hope of success to smithereens. The most common mistake I see in these situations is the manager letting the negative voice go on too loud and too long before addressing or mitigating the situation. Negative energy can jeopardize the outcome of an entire team.
When you ignore or downplay the significance of a single person’s negativity, the result spreads far beyond that individual. Speak to that person, look for the cause, discuss alternatives, ask for support. Don’t let a small flame turn into a wildfire that destroys everyone’s best efforts.