Some years ago, my son managed to bump into me while I was in "All Mail" on my iphone. Everything got selected somehow, and I deleted EVERYTHING in my gmail account. It was from literally the very beginning of gmail. At the time, this was basically unrecoverable. 

Over the years I have had exactly two occasions where I needed anything from all those emails, and it was only a minor inconvenience those two times.

Just seemed like a relevant story. 😂