Team PerformanceWhen a member leaves the project or is added mid-project to the team, that team’s composition changes. Consequently, the team performance increases or decreases. If the team performs worse after the change, the project manager must find a solution. The first step is understanding why changing team composition affects performance.

Sometimes, the team performs worse because the new team members are not skilled or experienced enough. But when they are, the team should perform better; however, that does not always happen. Even adding experienced and skilled members can decrease team performance, at least initially.

Team Development Stages

Team underperformance is likely to be caused by a mix of factors, unique to each team. One of the main causes is the alteration of group dynamics after a member enters or leaves the team. A modified team acts as a newly formed team. To understand group dynamics, Bruce Tuckman (1965) proposed four stages of team development: forming, storming, norming, and performing.

  • Forming – Individuals start to form the group; individuals avoid conflicts because they want to gain group acceptance.
  • Storming – Individuals start competing, and conflicts arise because individuals define their roles and establish the group’s hierarchy.
  • Norming – The group is focused on problem solving and respecting procedures; individuals trust each other.
  • Performing – The group performs well as a team. (Not all teams reach this stage.)

Group vs. Team

If the composition changes when the team is in the norming or performing stages, the team recedes to storming or even forming stages, which can explain the decrease in team performance. The project manager wants to get the team into the norming or, ideally, performing stage. Doing so implies not only an understanding of team development stages but also of the difference between a group and a team.

A group equals a collection of individuals with varying skills, experience, and personalities. Even a group of highly experienced and skilled professionals may not work well as a team. A group becomes a team when individuals have a common identity, interact and communicate effectively, work toward the same goal, and start thinking of themselves as a team rather than as a group of individuals. A project manager needs to identify what motivates those individuals to act as a team.

It can take a long time for a group of individuals to start acting as a team. It can take even longer for the team to go from forming to performing stages. But it only takes adding or replacing a team member mid-project to disturb the team dynamics and, in some cases, make the team recede to the forming or storming phases. To avoid such changes, which can lower performance, an accurate initial selection of the project team is essential.

Sometimes team changes are unavoidable, as employees come and go from organizations all the time. This is why motivating employees to remain in the organization and investing in team building can help project managers retain talent and avoid changing the project team too often.

Cristina Neagu

Cristina Neagu, PhD, is a freelance editor and proofreader, and a Certified Associate in Project Management. She loves creative writing and managed a virtual team of writers for three years. When she's not working, she likes to read, spend time outdoors, and travel. Visit her website,, or contact her on LinkedIn.