If you went to a concert to see Lorde and instead Ed Sheeran emerged on stage, you might be pleased to see him, but disappointed because Ed Sheeran is not Lorde and is never going to do the version of Green Light you thought you’d be watching.

The fact that Ed Sheeran is not Lorde demonstrates the economic principle of fungibility. If something is fungible, it means it can be exchanged for a good of equal value. Money is said to be fungible, because it can be exchanged easily for goods of the same value. Around the world, $4-5 can be swapped for a Big Mac. However, Lorde is not fungible.

Although this seems to be common sense, the many incompetent managers, team leaders, or coaches in the world completely fail to understand it. They look at the members of a team in the same way they see batteries in a torch or a tool: a technical skill that can simply be exchanged. While a football team requires a striker, a wing, and a goal-keeper, competence is all that is needed to change out one player for another using this line of thinking (fungibility). But that’s incorrect. Players are more than mere functional capability, and arrive on the field with personalities, styles, and preferences. Messi is not Neymar and both are very different players to Wayne Rooney.

Scientific evidence indicates quite clearly that individuals’ personalities play a significant role in determining the performance of the team they play with. Personality impacts team performance as much or more than pure technical skill and, when combined, team members’ personalities operate like the different functions of a single organism. A meta-analysis showed that team members’ personalities influence:

• cooperation
• shared cognition
• information sharing
• overall team performance

There are often substantial compatibility differences between people on the team, regardless of how similar their expertise or technical backgrounds. Suzanne Bell, a psychologist working on the Mars project for NASA, points out that astronauts are intelligent, they’re experts in their technical areas, and they have at least some teamwork skills, but “what’s tricky is how well individuals combine.”

People aren’t fungible because they play two roles in a working group: a functional role, based on their formal position and technical skill, and a psychological role, based on the kind of person they are.

Because so many teams miss the psychological synergy required to perform, my colleagues and I developed a method to look at teams as a function of their psychological roles, exposing the deep dynamics of the group. We found team members occupy one of five roles:

• Results.Team members who naturally organize work and take charge tend to be socially self-confident, competitive, and energetic. 
• Pragmatism.Team members who are practical, hard-headed challengers of ideas and theories tend to be prudent, emotionally stable, and level-headed. 
• Innovation. Team members who naturally focus on innovation, anticipate problems, and recognize when the team needs to change tend to be imaginative, curious, and open to new experiences.
• Process.Team members who pay attention to details, processes, and rules tend to be reliable, organized, and conscientious.
• Relationships.Team members who naturally focus on relationships, are attuned to others’ feelings, and are good at building cohesion tend to be warm, diplomatic, and approachable.

Looking at the balance of roles in a team offers an extraordinary insight into its dynamics and can predict the probability of success or failure for an assigned task. For example, a finance team was charged with rolling out a novel business reporting product for transforming the culture of a government agency. But, the percentage of players in each role showed the team was doomed from its inception:

• 17% of team members were considered results-oriented (low)
• 100% of team members were considered pragmatic (high)
• 0% of team members were considered innovative (low)
• 50% of team members were considered process-oriented (good)
• 0% of team members were considered good relationship builders (low)

This team failed because no one played the relationship-building role, the team lacked internal cohesion, and they failed to establish any connection with the frontline leaders who were required to take on the team’s new accounting process. With low-results role players and a team full of pragmatists, the group moved slowly, reluctantly, and waited to be told what to do.

The mix of the right personalities can make the difference between a competent performance and a great one. A Lorde single featuring Ed Sheeran might be a good example.

My new book on teams is “Fusion: The Psychology of Teams.”