I picked this up from listening to 'More or Less' on BBC Radio 4 (podcasts are available here http://www.bbc.co.uk/programmes/p02nrss1/episodes/downloads).
Since I got a large (multiple gigs) allocation of eMail space, my archiving/organising of email has effectively fallen to zero. I can search for people and subjects and grab the threads I need most of the time.
I get pushback on this approach from the 'Inbox Zero' brigade but it seems to work for me - after all, I don't organise my twitter or facebook feeds - I just let them scroll by - same with eMail - it'll be there when I need it.
Finally I have some support for my approach - and from IBM Research no less! MIT Technology review introduces and links to the research paper here: https://www.technologyreview.com/s/424056/stop-organizing-your-e-mail-says-study/
As with all things, your mileage may vary but at least I can feel less guilty about the '>999' message count on my mail icon . . :-)