By definition, agile development is a team sport. The emphasis is on teams working and delivering together. It’s not measured by how many user stories the development team produces, but by how many completed/done stories the team can produce.
Quality is not something “owned” by the testers, but the responsibility of the entire team. In fact, you don’t try to “test in” quality, but rather “build it in”.
It places collaboration and teamwork above individuals working alone. It values pairing and swarming around work. It values limiting WIP so that team members work together.