What is DELETE CHANGE HISTORY button on Audit History view (see it only in PROD but not in SANDBOX)

I noticed the "DELETE CHANGE HISTORY" button (see the screenshot below) on the Audit History page related to a specific record.

It is available only in PROD environment and not in SANDBOX environment.

I have logged in as System Admin in both environments.

Questions:

1. What is this button and what does it do?

2. Why do I see it only in PROD and not in SANDBOX?

Thank you.