In accordance with Scrum theory, a group of 100 people should be divided into multiple Scrum Teams by understanding the product, the product vision and the rules of the Scrum framework, and then dividing themselves into teams because:

It respects the self-organization and empowerment of the people. The people are the ones who have the knowledge, skills, and experience to create and deliver the product. They are also the ones who will work together as Scrum Teams, collaborating and coordinating their efforts. Therefore, they should have the autonomy and authority to decide how to form their teams, based on their preferences, interests, and capabilities.

It supports the alignment and coherence of the Scrum Teams. The people should have a clear and shared understanding of the product, the product vision, and the rules of the Scrum framework before forming their teams. This can help them to align their goals and missions, to ensure that they are working on the same product and towards the same vision. It can also help them to follow the same principles and practices of Scrum, to ensure that they are working effectively and consistently.

It fosters the collaboration and synergy of the Scrum Teams. The people should form their teams in a way that maximizes their collaboration and synergy. This can mean choosing team members that complement each other’s skills and strengths, that have good rapport and trust, that can communicate and coordinate well, and that can deliver a valuable Increment each Sprint.