A Short History of The White House Email Retention Policies

The Washington Post gives a thorough rundown here.

A shorter rundown would go something like this: the Clinton administration, after getting into trouble over losing some White House emails, had a perfectly good system in place by the end of its term. But the Bushies threw that out the window for no apparent reason when they came in and didn’t put anything in its place. Whether deviousness or incompetence is to blame is unclear.