Optimization provides possibility turn the plant inactive. However non-optimized sites does not have this feature. This causes non-active plants to appear on drop downs and in selection screens which causes clutter look.
Part of concrete businesses to have smaller plants that can be carried here to there based on the demand. Or seasonal they can be opened or closed. Business does not want to use same plant number. Removing master data never good idea from so many perspective. There should be way to make the master data inactive to avoid this clutter.