I'd argue that HipChat, Campfire and Yammer all "lost" to Slack because they weren't moving fast enough.
This Google trends line is interesting: https://www.google.com/trends/explore#q=slack%2C%20hipchat%2...
This Google trends line is interesting: https://www.google.com/trends/explore#q=slack%2C%20hipchat%2...
Some startups forget that the first impression and cool factor still play a big role in creating a huge buzz about your app.
I preferred Skype instead of using Hipchat, that's how bad it was.
You're splitting hairs. They are both chat apps for crying out loud.
Slack grew as fast as it did because it got pimped to us by VCs and thought leaders and then wannabe thought leaders and down all the way to the bottom rung of the societal ladder. Great strategy by Slack but there is nothing special about it (the product).
About Yammer, I wouldn't really put it in the same bucket as Slack, as it really tries to be a Facebook for your company, not a group chat.
Slack came very late and yet still managed to eat the others.
That seems like an argument against the idea that "being slow will kill you".
It's true though - Hipchat was caught napping. Atlassian backburner'd it at exactly the wrong time, and by the time they starting fixing things, it was too late.
This being said, Atlassian isn't really a 'startup' anymore. Hipchat is a side-product of a suite of gorilla products.