The practical starting point
A message archive can grow because nobody owns the decision about keeping it. Record the purpose, responsible person and review trigger for each type of information. A general wish to keep everything may hide records that no longer support any active task.
A workable next step
Review legal, contractual and operational requirements with the appropriate responsible people before choosing a retention period. Do not invent one universal number for all datasets. Document how the approved decision will be applied and checked. The useful output is a maintainable process with a clear owner, not merely a policy sentence that the underlying storage never follows.
Keep in your notes
- Identify the continuing purpose.
- Check relevant obligations.
- Assign implementation responsibility.