Monday, November 17, 2008

A Model of Your Inbox

I've been thinking a lot about how users view and manage their inbox. This post is about the model I came up with. I'm basing this on my own experience and on having talked to dozens of people about their email habits. But since this blog also is read by lots of email enthusiasts, I'd love to hear your feedback: Does this make sense? What am I missing?

Four Quadrants

Every single email message youreceive can be classified into one of the four quadrants below. Important emails are the ones you need to take action on. Urgent emails are time-sensitive. Urgency does not necessarily imply importance: Your coworker's cake will be gone in a few minutes, but it's not necessary to take action on that, especially if you're on a diet.

The key insight here is that the stuff you care about are the emails on the left. These are the emails that make it worth checking your Crackberry every few minutes. They emails that keep you awake at night.

Filtering the Important

How can you filter out what's important? My theory is that for humans, that's actually the easy part: You often easily determine importance by just looking at the sender of the message. Roughly, senders fall into three categories:
  1. Crap: these are easy to remove: iTunes Receipts, Amazon notifications, LinkedIn emails, frequent flier statements, and the like. Not important.

  2. VIPs: You know who they are! Major customers, your manager, and your girlfriend belong in this category. Important.

  3. People you know: These are the non-VIPs that you still want to deal with. I like to think of this category as the intersection of your Facebook and LinkedIn connections. Mostly Important.

  4. Everyone else: Recruiters and salespeople, senders you don't recognize. Mostly not important.

Research indicates that people use senders as their main importance indicator [1, 2]. The task of filtering out important email is easy, and you could probably train a classifier to very high degrees of accuracy.

Managing Later vs. Now

I believe that this is the heart of email overload. Remember how I said that the left side is what matters. I like to label the two subcategories as "Later" and "Now" [3].

The workflow should be that you decide whether you want to deal with an email now or later. You respond to the "now" emails and they disappear into the archive. The "later" emails haunt you until you're done with them.

This is the point where today's email clients fail. Users try various mechanisms to manage now/later and to do/done: Keeping emails unread, starring them in Gmail, and filing away stuff that is done into an intricate foldering system. The number of email management strategies that users come up with impressive [4].

But none of this works. Emails that are unread and starred disappear from your main view. Out of view, out of mind. Poof. There is no pressure to act upon them. In contrast, filing away emails that are done requires an amount of discipline that few users have. I think that the inability of managing now/later and to do/done is one of the main reasons for email overload.

Wrapping Up

Let's review. I've outlined three theories here:
  1. Your incoming all fall into one of the four quadrants of urgency and importance. What really matters is the important stuff, which breaks into "Later" vs. "Now".

  2. It's easy to filter important vs. not important.

  3. It's hard to manage Later vs. Now because the current tools are broken.

I'd love to hear your views on my theories. Drop me a line or leave a comment.


[1] Gina Danielle Venolia, Laura Dabbish, JJ Cadiz, and Anoop Gupta. Supporting email workflow. Technical report, Microsoft Research - Collaboration and Multimedia Group, September 2001.

[2] Olle Baelter and Candace Sidner. Bifrost inbox organizer: giving users control over the inbox. In NordiCHI '02: Proceedings of the second Nordic Conference on Human-computer interaction, pages 111-118, Aarhus, Denmark, 2002.

[3] The "Getting Things Done" school of thought has a more intricate system than this, but I think that Later / Now is the essence of it.

[4] Steve Whittaker and Candace Sidner. Email overload: exploring personal information management of email. In CHI '96: Proceedings of the SIGCHI Conference on Human Factors in Computing Systems, pages 276-283, Vancouver, British Columbia, Canada, 1996.


Aga said...

Hi Gabor,
I am researching email prioritization for my PhD and I have arrived to conclusions that are very similar to yours. People, indeed, distinguish between urgent and important mails. One additional dimension upon which people judge what to do with an email that I've noticed was time required to answer the message. If the answer was quick, people tended to deal with the email right away (even if its content was neither urgent nor important) as a way to avoid remembering about unanswered emails. Moreover, the social grid seems to be extremely important in deciding on what to do with an email. there is quite a few more interesting articles about the subject. I could send you the references if you would like.
Aga (currently at Google in Zurich:)

Norbert Toth-Gati said...

Hi Gabor,
I just want to share my mail-experience in relation to your theories: people I know do filter often by names, and tend to prioritize by names; I star my mails, but unfortunately they get out of my main view and get forgotten easily; i have tried to tune my gmail to only notify me on important mails. For not losing the important mails out of sight, an ideea would be for the inbox to have this special section for such emails, which always stays in the main view.

Itzy Sabo said...

Hello Gabor,

I believe that your use of "later" is hiding an additional, deeper problem. "Later" suggests that the main issue is timing. I would argue that the main problem is not one of timing -- it is the fact that people find it difficult to decide on an appropriate course of action with regard to many messages. So "later" does not mean "I'll do it later" -- instead it's "Later on, I'll try to decide what I need to do." Because it is much easier to act on the clear, self-explanatory messages that have an obvious, "correct" course of action, the messages that require additional thought will forever wait until "later." As a result, messages scroll out of view never to be seen again...


Itzy Sabo

Gabor said...

Thanks for all the great feedback!

Aga: What do you mean with "social grid"? Is this just the social network or a concept I'm unaware of. Please do email with more thoughts.

Norbert: Yeah, a "later" section in the main view of the inbox might be a good idea. The problem is that people easily train themselves to just ignore that section. Not sure how to provide sufficient pressure to make them actually handle those items.

Itzy: Yup, there is the "I'll decide later what to do" subcategory. I'd guess that 60% of my "Later" emails are actually in that part. I wonder if differentiating between "decide later" and "later" would be valuable and, as always, how we could maybe automate that process :-)

toblux said...

Hi Gabor,

keep in mind important emails that contain both an urgent (now) as well as a not so urgent (later) message/task, and thus fall into two categories.

You might act and fix the servers immediately, but you'll probably just forget about the board slides review unless you are either very disciplined or your email program knows how to deal with this properly.

Cheers, Thorsten

Markus said...

I agree that the mail overload results from too many "later" mails. And I guess the consensus of many email management strategies is that keeping these mails in your inbox is a recipe for disaster. Most strategies rely on keeping the inbox empty at all times, converting any "later" mails into tasks that can be properly prioritized in a task management system.

Come to think of it, it is strange that gmail does not offer any help for these scenarios. In fact there are numerous Outlook plugins for email management but I have not found anything similar as a webmail service.


Jonathan Tang said...

Couple quick observations from my own experience:

1.) Oftentimes, it's not a discrete divide between "urgent" and "not urgent", but a particular time window that the e-mail must be responded to. For example, if a recruiter in California sends me an e-mail at the end of their workday, I don't need to respond to it immediately, but I should get back to them before they get into work the next day. Or if a friend sends me an e-mail, it's not really "urgent" or "important", but I want to get back to them before a socially awkward period of time has passed (usually a day or two). Sometimes the required time period will be obvious from the context of the e-mail, other times it'll be a little fuzzy.

2.) I wish someone would solve the problem of e-mail dependencies, i.e. when you're having a conversation with one person, and in order to get back to them, you need information from another person. Their are a lot of contexts where this arises, eg. you're dealing with a recruiter, but you want to hear from other companies before you move forwards. Or you're working on a technical project, somebody asks you a question, but to find the answer, you need to get a bunch of passwords from a server admin. It's really easy to forget "Oh, what did I need this for?" when you finally get the information that's holding everything up.

3.) There should be provisions for mixed media (eg. blogs, forum comments), since many of them suffer from the same issues. For example, I wasn't initially going to comment here because I'd like to get back to coding, but I knew if I didn't, I'd just forget about it and wouldn't bother. I wish I could've starred this blog post and said "Come back to it tonight, when you're burnt out from coding".

Andy said...

I can think of one type of emails that are important, but don't fit in in your scheme: sign up notifications or other info you wanna keep.

I have:
1 - Inbox (answer today)
2 - Hold (answer required sooner or later, or still needed for an ongoing task
3 - Archive

The really urgent/important ones will be answered right away, so they fit into 1.

All the rest is done with labels...

Sean Horn said...

The Chandler project people seem to be thinking along the same lines for notes. Their email interface is vestigial, but the whole program operates on this important/not important basis:

Turph said...

The boxes of priorities are correct, but there is still all this work assigning rules and managing this. Too cumbersome and again - I am working in another silo.

I have long wanted to be able to manage this based on my Address Book. In my address book each person, (or company, or job number or group, etc) could be given a sliding value. This management is more in line with what I want at any given moment.

Also, if it was more of a "cloud address book" why not have the same logic behavior run something like Facebook or Twitter? Let me determine who is important and when the notification trigger happens...

rokhayakebe said...

Hi Gabor,

I am not sure how to describe my email problems, but I do know one solution that would help me: Drag and Drop messages up/down feature.

I should be able to order my messages as I please and not just by Date/Time.If I had that half of my issues are solved.

topfunky said...

When possible, I use a bug tracker to manage Later items. I can prioritize issues and keep my inbox close to zero.

Anonymous said...

"The 7 Habits of Highly Effective People" by Steven Covey.

One of the best selling books of all time.

Has basically that exact chart in it.

Might be worth flipping through so you don't waste time reinventing the wheel.

Gabor said...

Thanks for all the feedback, guys!

rokhayakebe - so how would you then reorder your messages?

topfunky - good point about the bugtracker. Do you find that you're disciplined enough to put the Later items in there?

Anonymous - thanks for the pointer. While Covey has a similar importance vs. urgency matrix, it's for tasks in general. IMO, applying this model to your inbox yields something pretty powerful.


Anonymous said...

maybe the problem is not email overload but work overload.
People just don't have time to do all their "later"s... until their boss comes in and remind them about it. Then it becomes "urgent", so urgent they don't have time to remove the email from the "later" folder once it is done.

Niall Smart said...


Couple of my belated random thoughts:

* Sometimes what we think is important actually isn't. What's great about twitter is that it doesn't have an unread count - history just scrolls off the bottom into oblivion. How can you apply that model to email?

* I identify with what Itzy Sabo says - a lot of the time, mail stays in the Inbox because of the prevarication: I'll decide later. I'd posit that one of the main reasons for this is that the usual list of actions associated with email is inadequate (Reply, Forward, File, Delete) We need a richer context sensitive set of actions (File Bug, Snooze, Create ToDo, Bookmark, Search) that match the cognitive decision making process of what to do.


Anonymous said...

Hi Gabor - This is a reply to Marcus. There is a really good Outlook plugin that I found. Outlook Track-It is my savior right now. Everything is right there, including new followup functionality. is where I found it.


chadmany2k said...

thanks for this. I use outlook, so i just found Outlook Track-It, which is a toolbar plugin that reminds me to follow up to emails. its been great for personal use too.

Christine said...
This comment has been removed by the author.