Explanation
One for all users, one for the research department, and one for the marketing department.
Note: What are Deployment Groups?
With Deployment Groups, you can orchestrate deployments across multiple servers and perform rolling updates, while ensuring high availability of your application throughout. You can also deploy to servers on-premises or virtual machines on Azure or any cloud, plus have end-to-end traceability of deployed artifact versions down to the server level.
Reference:
https://devblogs.microsoft.com/devops/deployment-groups-is-now-generally-available-sharing-of-targets-and-mo