Slack has opened its Australian office as the internet chat service sets its sights on growing users in the Asia-Pacific region.
Slack competes with technology behemoths Google, Microsoft and Australia's own HipChat from Atlassian by using intuitive smart messaging in a bid to "kill emails". 
  Unicorn status   
It's rapid take-up has resulted in Slack being touted as a "unicorn" company worth more than $1 billion after a $2.8 billion valuation last year.
However, Slack co-founder Cal Henderson says success for the chat service and 2.3 million daily active users only has come after a "traumatic" failure.
Clad in his trademark check shirt, the serial entrepreneur is in Australia for the first time for Thursday's launch of the Slack office in the old Carlton Draught brewery in Melbourne. 
He describes Slack's valuation, which may edge closer to $5 billion, as "a ludicrous number". 
"But on the other hand, maybe compared to some other unicorns in other industries, we have a very straightforward business," he says. "It's not speculative how we will make money one day. We make software that we sell to customers; it is a very simple value proposition and it is a proven industry".
Slack's turnover was $64 million last year.
Henderson says he's focused on meeting expectations. 
"Whether anyone had come up with that [unicorn] label or not, valuations of that size put pressure on companies to deliver," he says.
  Finding success in failure   
Henderson is a Silicon Valley veteran, as a founder of photo-sharing company Flickr. It was sold to Yahoo! for about $35 million in 2005.
In 2009, he co-founded Slack with Eric Costello, Serguei Mourachov??? and Flickr co-founder Stewart Butterfield.
"There are four founders of this company and we've been working together for more than a decade," Henderson says. 
The genesis of Slack came from the founders' failed video game start-up, Glitch, just as Flickr was a pivot from a failed video game, Neverending. 
"There is a very common thread of failed video games turns into something else that we weren't trying to do which turns out to be successful," Henderson says. "So our vision of making the video game that we wanted to, which has failed twice now, has driven both of the successes." 
At the time, both failures were "terrible and traumatic".
He attributes Neverending's failure to the environment in that period but says "second time around, we had everything going for us and still f---ed it up, so I guess we are just not very good at making video games".
British born and bred, Henderson says he's had to adopt a Silicon Valley mentality to survive the experience.
"It's definitely the case that anywhere outside Silicon Valley, failure is not embraced," he says.
"The reason Silicon Valley has been so successful, and is the way it is, is because failures are celebrated as part of the path to success. I think that's super important because Slack wouldn't have existed if we hadn't failed at making the game and tried to do something else."
After shutting down Glitch, the founders had a "whole bunch of things" they considered pursuing. 
"Slack wasn't the thing we were definitely thinking about doing," Henderson says. "It was just one of the choices."
Propelling Henderson towards Slack was his desire to continue to use the chat service himself.
"We knew when we shut the game down that we wouldn't want to work without a system like that again," he says.
"We knew it worked really well for us as a collaboration tool. We thought maybe it would work very well for other teams like us. We didn't have a vision of where Slack is today with millions of users, we thought it might be a viable business that people might use."
  Freemium model   
Slack's fast uptake can be attributed, in part, to its free pricing at entry level. The freemium model is generous enough that most businesses won't need to upgrade to a paid option although an enterprise option aimed at businesses with more than 10,000 staff is in the works.
"Part of the reason it has been successful has been luck on our part and the timing of a confluence of changes in the consumer messaging space," Henderson says.
"Ten years ago, people would email each other outside of work and now with iMessage and SMS and Facebook messenger and WhatsApp and Google Talk, people are using a variety of messages to communicate with different people."
Henderson says Slack is bringing what's happening in the consumer space to the business space. 
"Slack is offering a way to take all the disjointed ways people communicate and put them into one place," he says. "Whether you are trying to talk to someone who's on mobile or someone at their desk, instead of having different tools for each person you talk to, it's a single place that brings people together." 
Ten or 20 years ago, a business would be a Microsoft devotee and get all its tools from Microsoft, which, Henderson points out, was very hard to unseat.
"Now that is not really the case," he says. "Businesses often use tools from 10, 20, 30 different vendors for all the parts of the business.
"Slack is a way to tie all those tools together; if you use Jira for issue tracking, Salesforce for sales or NetSuite for accounting, they are made better from using them with Slack." 
Henderson admits Slack's shiny new Melbourne office is "mainly a customer support office" but says Australia is important for the tech company.
"About 20 per cent of our users today are in APAC, so it's a big growing market for us and it's a great place to be in the time zone," he says. 
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