
The first question I asked Slackβs CEO and co-founder Stewart Butterfield was a selfish one: when will the app get threaded comments, so TNWβs editorial team can use it full time.
Sadly, he could only confirm that theyβre βcoming soon,β one of a bunch of new features that the app, which hit a $1 billion dollar valuation late last year, has in the pipeline.
Onstage at the DLD Conference in Munich, Butterfield confessed that he doesnβt exactly know why Slack has succeeded: βI get in trouble with my PR team for saying this. But I have no fucking idea.β I suggest maybe the missing ingredient in other communication apps was βfunβ. Butterfield agrees thatβs definitely part of it:
βOur team has been around these things long enough to know that we want to build a platform that lets people put their own twist on it, so that people get that satisfaction from it. All of our growth so far has been word of mouth recommendations. If we didnβt have that, weβd have nothingβ¦as well as getting work done, thereβs all the bullshitting people do.β
Earlier this month, on the same day that Slack unveiled the details of its Slack Plus plan, Facebook pulled the dust covers off Facebook At Work. While Butterfield acknowledges that he hasnβt seen that product in action yet, heβs not worried:
βThe brand βFacebookβ is not, I think, well suited to being used for work. The product sounds like it might be really useful at a really large company. Obviously, if itβs a seven person company, thereβs not much point in creating a profile. But if itβs a 100,000 person company, then thereβs certainly some value in having that.
When I think about our larger customers, the bigger corporations and large startups β Comcast, Sony or Dell say or Airbnb and Stripe β itβs hard to imagine the teams at those companies opting to use Facebook At Work instead.β

Butterfield says he focuses on what Slack can do to be better, not what potential rivals are working on. Itβs a fairly common sentiment to hear from CEOs but it sounds genuine coming from him: βIβm not worried. If weβre paying too much attention to what our competitors are doing and being reactive, itβs not likely weβll make the best decisions for our customers.β
Why didnβt previous communication apps think of some of the user-friendly features Slackβs implemented? Butterfieldβs answer is blunt: βWeβve learned from experience that people donβt give a shit about your startup, thatβs the bottom lineβ¦we try to be mindful of peopleβs needs and the pacing of their day, ultimately to be as courteous as possible.β
He compares his vision for Slack to βa well-run hotel, one where you can tell a lot of thought has been put into the details.β As the hotel manager, heβs not afraid to highlight where things could be better. I ask him what feature most needs to be fixed in Slack and, after confessing that thereβs a long list, he concludes:
βThe biggest thing is probably performance in the mobile app. Weβve been working for about six months on a complete rewrite of both iOS and Android apps to allow offline mode. Itβs a difficult, complicated project but itβs one of the things that drives me most crazy because I travel more than most people in our team and use the mobile app more than most people in our team.β
With incredible growth, plenty of investment and glowing press, one of the most common questions Butterfield gets is not about how Slack works but when heβll sell it. But after selling Flickr to Yahoo! in 2005, he says letting go of Slack is a lot less likely:
βThe math is a little bit tough to make work. At some price β if someone offered us $100 billion tomorrow β it would be pretty hard to say βnoβ because itβs just not me. At some insanely high number weβd have to consider it but that doesnβt make sense for any acquirer. Thereβs a disconnect between the amount of money it would make sense for them to spend to acquire us and the amount of money we could make by becoming even bigger than them someday.β
Reflecting on the current state of Yahoo! under Marissa Meyer, he isnβt hopeful: βI think Yahoo! has most of the same challenges now as it had when I left in 2008. It had much more promise in 2005. In retrospect, everything is obvious, but Yahoo! had a lot of potential that it squandered in the years I was there.β
One thing Butterfield did learn at Yahoo! was how terrible most workplace software is to use. It was his first job at a big company and he recalls: βI was literally astounded by how bad all the internal software was. I hadnβt used that kind of software before so I hadnβt realized how terrible it was. And that was definitely something we thought about when we were starting Slack.β
One of the secrets of Slack goes beyond offering chat rooms for teams. By indexing all the documents shared through it and the discussions around them, it can become the institutional memory so many organizations usually squander. Butterfield says :
The searchable memory is absolutely critical but itβs hard to sell on that basis. No one knows they need it but once they have it, they canβt live without it. Slackβs default is transparency and itβs easier to catch up on 100 Slack messages than on 100 emails. When you join a company with email, you start with an empty inbox. When you join Slack, you see every document, discussion and decision thatβs been made.
As for all those articles naming Slack as the prime suspect in the imminent death of email, Butterfield says βthatβs just a convenient headline to talk about Slackβ. He knows that email β βthe lowest common denominator communication methodβ β isnβt going anywhere. He just wants more people to check into the comfort of Slackβs hotel and visit their inbox a little less.
β€ Slack
Image credit: Picture Alliance for DLD
Read next: A Community of Startup Founders Grows on Slack
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