Very few entrepreneurs have been are able to successfully create a viral, cult-like following around something as random as workplace collaboration software. But, if anyone could — it would be Stewart Butterfield, a two-time failed gaming entrepreneur.

When headlines circulated that Amazon was looking to spend some $9 billion to purchase Slack, it was another sign that this hot app wasn’t some overblown unicorn flash in the pan.

While Slack has a high valuation, it stands out from the current startup landscape. In a world of 24/7, party all night brogrammers, Butterfield says his offices are empty at 6:30 every night, and people work ~45 hours a week. He’s designed the company for people who have already lived the insanity of a boom and bus...