https://sforcemaximizer.com/how-to-design-a-system-of-record-across-multiple-objects-in-salesforce-multiple-entry-points-one-source-of-truth/

If you are an architect, admin, developer or aspiring architect wondering about duplicate data in Salesforce spread across objects , having issues with users complaining which object to rely on master record, my blog provides you a framework to decide system of record across objects and come up with a solution with minimal downstream impacts.