Internally, a lot of companies have a standard corporate damage-limiting process that actively deletes old email. You can't have subpoena'd data you really no l

Internally, a lot of companies have a standard corporate damage-limiting process that actively deletes old email. You can't have subpoena'd data you really no longer possess. That's a (potentially significant) legal win. OTOH, if you claim you've gotten rid of data to one party, and then another party is able to dig that same data up in a legal proceeding, I expect the first party might be upset, and seek compensation. Quite apart from that, if you have metrics that show long tail data are infrequently accessed, but do take up an appreciable (and ever growing) amount of resources, it's a OpEx/engineering win to actually get rid of that on a proactive basis.