What made Slack successful

And why it’s on a hyper-growth phase

by Ujjal Pathak

This past August, Slack hit its two-year mark as a company with a successful product. Within two years, they have grown to 1M+ DAU with a $3B valuation (for comparison, Facebook was valued at $500M within two years of its launch with ~6M DAU).

Why such a growth? Well, Slack is one of those products that just works. Dropbox and to some extent Uber are other consumer-facing products that also fit in this bucket. They have all done a great job keeping the main thing the main thing. I have been following their growth as a user since their early days — been using Slack since early 2014, Dropbox since its private beta in 2008 and Uber since 2011. Heck, apparently, I’m one of Uber’s top 100 spenders per their unofficial leaderboard. Not sure if that’s an achievement worth bragging about but more on that at a later time. But today, I just want to talk about Slack.


Many don’t know that Slack as a company was originally founded as Tiny Speck, which produced a beautiful, cutesy, crafting MMO called Glitch. One of the interesting features on Glitch was the ability for users to create/join groups and chat with each other in real-time. It was fun and quirky. And to some of us busy building games on Facebook’s platform, it was quite innovative and refreshing. One could say, birth of Slack started right there. The game eventually sunsetted for many reasons, but most noticeably (if my memory serves me right) for not relying on Facebook Open Graph from the get-go unlike other social games from Zynga and Playfish. The game failed but the team didn’t give up. They took what was successful from an Engineering-standpoint (a kick-ass RTMS), iterated, partnered with MetaLab (I know these guys and they are extremely talented) and launched Slack. I highly recommend reading Stewart’s memo to his team two weeks before Slack’s preview release. Very inspiring.


We have been using Slack for a while here at @Walmart Labs. Until recently, Walmart Labs was Slack’s biggest client. I believe Comcast is now their biggest client. Apparently, Slack’s userbase is doubling every three months.

Google Trends on Slack

People have talked about why Slack’s been so successful. I would love to add my two bits into that discussion:

It’s an extension of existing relationship — Twitter is hard to learn and use. If you haven’t already read Chris Sacca’s post on it, I highly suggest you do (warning: it’s a long read). David Levine also recently talked about it and what he said is so true — Facebook works because it’s an extension of existing personal and social relationships into a better UI, whereas Twitter et al. help create new relationships, which takes a lot of effort and time. Slack is just like Facebook — it’s an extension of existing work relationships into a better UI.

It’s perpetual — You can’t stop thinking about Slack. People at work go to appointments and vacations and guess what they put in their OOO notice? “I can be reached via Slack” — and not on their phone, not via email — but on Slack! It’s that constant reminder that new things are happening on Slack — and you better come check it out. Lines like these are very common at work: “Did you see that on Slack”, “I posted that on Slack”, “I just Slacked you this file”, “Can you check my Slack message?”, “Please check Slack for next updates”, “There’s a new channel for React.js”. How often do you hear your friends say “I posted my vacation pictures on Facebook”. You don’t.

FOMO on Slack is FOGF — On weekdays, I spend more time on Slack than on any other app, including Facebook and Twitter.

FOMO on Facebook and Twitter is very ephemeral and there are ways to un-FOMO yourself. Didn’t check Twitter for a few days? Not a problem! Twitter offers While you were away. Didn’t check Facebook for a few days? No worries. Facebook News Feed is always defaulted to Top Stories.

Didn’t check Slack for a few days? Well, you can’t. But even if you do, you have no option but to revisit all the older Slack messages that were posted in a chronological order. It’s a big PITA. The end of result of FOMO on Facebook and Twitter? Friends complaining or you not being able to carry on a conversation in a social setting due to lack of context. What about that of Slack? Well, you will be called out as a bad team-member or in extreme worst-case —potentially get fired (I hope this never happens!)

Different usage scenario — My teams (current and former) have used various communication tools — and it always felt like we were made to use ‘em and communicate when shit hit the fan. With Slack, it’s different. We use it to make sure shit doesn’t hit the fan. My current team is a distributed team. They are not on Slack because of any social pressure — they are there because there’s an implicit understanding that Slack helps get things done faster and better as a team. In fact, we encourage over-communication on Slack. Most of the times, I have noticed that after the daily standup, we say “let’s carry on the conversation on Slack”— and not on the conference call. That’s a pretty strong indicator that Slack is so powerful.

It’s fun — For the 100th time, Slack indeed makes work more fun. I have used more emoticons (and Giphys) on Slack than on Facebook. Being in the e-commerce industry, we are busiest during holidays such as Thankgiving and Christmas. When our OPMs (orders per minute) keep going up on those days, guess where we party and celebrate? On Slack! Our #Holiday channel last year was so successful that someone created #Holiday-2015 a day after last Thanksgiving. Thomas Watson once said “Good design is good business”. When I see/think of/use Slack, I have to take it another level and say it’s a happy design. And Happy design is great business. Happy design treats users as friends (when I interned at Nike, we were told that Nike designs for people, not users, not consumers). As Andrew Wilkinson (founder of MetaLab) said: “Slack acts like your wise-cracking robot sidekick, instead of the boring enterprise chat tool it would otherwise be.” Slack is a B2C software designed for the B2B world. And it seems like Facebook is trying to do the same.

Smart launch strategy — When Slack launched publicly, they went live on Day 0 with apps on both iOS and Android platforms. It took a year for HipChat and Dropbox to extend support on mobile.

In a few years, if Work/workspace as a Service (WAAS) even becomes a thing, Slack is going to be the first, successful WAAS!

What’s next?

Slack doesn’t have to build new features around retention, unlike other social networks. Retention will never been an issue as the “system” will make sure employees use Slack every day. But it can build features that can help position itself as a true WAAS and target a bigger audience facing issues more than just around team communication.

When I look at Slack, I see it as a gateway drug to managing repository of various content. Not only it’s already replacing email, more and more files are being shared over Slack than via Dropbox or email. It’s slowly becoming the end all and be all of work communication thereby posing a real threat to Atlassian, Box.net and Dropbox for Business.

For example, let’s pick a small problem space — on-boarding. On-boarding new employees isn’t easy. Documents and important notes and conversations that help people ramp-up get lost in emails, on Confluence, Dropbox, Slack etc.

Did you know that up to $100K can be spent hiring someone and an average $10K is spent ramping-up a new hire? An average Bay Area BigCo hires a few thousands employees a year. Google and Facebook-s of the world hired close to 7K new employees last year. So if you do the math, millions of dollars are being spent ramping up new hires.

This is where Slack can help:

  • Enhance the #channel’s archive page to display all files shared within the #channel
  • When files are uploaded into the #channel, allow tagging (example tags: +new hire, +env setup, +sample jsons, +analytics, +product decks etc.) — and ensure they can be easily accessed from the new #channel page
  • Whenever someone sends a file to some of us in the team with <slack-channel>@<company-name>.slack.com cced., files should automatically show up in the new #channel page (there’s already an IFTTT Dropbox recipe for something similar)
  • Whenever someone in the #channel posts an explanation of a question and adds a tag (say +new hire), the post should show up on the new #channel page, specifically under +new hire tab
  • With smart LDAP/Active Directory integration, whenever a new employee gets added to the team distribution list, that person should get an email to sign-up on Slack and a link to the +new hire tab of the new #channel page

I believe the above can be refined further but you get the idea. Fix the on-boarding problem and it will solve all problems around document sharing and referencing. Let’s not forget that on-boarding never stops in an employee lifecycle. It’s perpetual just like Slack!

On a side-note: I would also like to see Slack get super aggressive on the Education field. In the US , there are 50M students and 3.5M teachers in K-12 and 20M students and 2M teachers in College. There’s a lot of opportunity to make it easier for students to interact with other students and with teachers. Remember early Facebook?

Disclaimer: If it’s not already obvious, opinions expressed here represent my own and not that of my employer

Update: surprised to see that this post got featured by LinkedIn on LinkedIn Pulse

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