Have you ever been working for a couple hours on a MailChimp campaign, then clicked the "Lists" or "Account" tab in the top navigation to check on something, then realized you just lost all your work? Or maybe you finished entering all your content, then forgot to save your work before logging out?
I’ve done that. Many, many times.
And I scream every time it happens. I guess the programmers got tired of hearing me scream, so they added a pop-up that warns you before you accidentally leave the content editor screen. I think they call them "Leave Alerts" but I call it the MailChimp Scream Blocker.