Time spent in pursuit of a pristine inbox is probably wasted. Don't you have anything better to do?
I whole heartedly agree. Why waster your time creating folders, naming them, and sorting them, and adding emails to them? All you have to do is search for them. Assuming your email client does a good job at that.
Outlook does OK at that finally, if it works. There are reasons why search in Outlook stops working. I gave up and 2 years ago went 100% gmail hosted for all my emails. I can search for emails from my original gmail account and pull up emails from 2004 - it's kind of fun to go back and see what was going on nearly 10 years ago. Try and make Outlook or Thunderbird save 10 gigs of emails and stay clean and searchable. Not gonna happen. Try to get Outlook to search through 108,000 emails like I have on my original gmail account. Ain't gonna happen.
There is one exception to not having folders: RULES. If you get a two hundred emails a day from LinkedIn people, blog post updates, internet marketing sales pages/offers, it's hard to see the important stuff. So I created rules to pop those directly into a folder. I peruse those maybe once a week. Maybe once a month. The point is, it's my choice when I want to go read those. Twitter followers is one that I pop into it's own folder - I get a lot of those and they are just distracting.
Instead of incessantly organizing your emails, spend that time setting up rules just once, over a week or two to dial it all in. Then you're done. All yo have to do is pick the emails you want to filter (gmail is great about that, much easier than Outlook) and it will filter similar emails. Check your rules folders every day for a week, to make sure they are working right, then you have an automatically organized inbox.
Personally I don't have rules for people. I see a lot of people setup email folders for everyone they know and don't know. I don't understand that at all. If I want to find emails from someone, I just search on their name. Why do I care if they are in a folder? Why would anyone?
Just convert to gmail and you will have the best, searchable, usable email on the planet, in my humble opinion.