Deployment and transfer of environments between people. Using docker images means that we can take the thing that developer A built and that "runs on their mac

Deployment and transfer of environments between people. Using docker images means that we can take the thing that developer A built and that "runs on their machine" (without necessarily having that developer on hand) and have developer B easily launch it on their machine without having any dependency or isolation or reproducibility issues, and after making some trivial changes put it in a new, fresh production server without having to ask the original dev how it was/should be configured.