The REAL reason Slack became a billion dollar company — Medium

The REAL reason Slack became a billion dollar company — Medium:

Why the Slacks alternatives didn’t work.
Now you probably think, yes but there was Yammer before, and Campfire and Hipchat and Skype. I’ve used them but none of them has been as addictive as Slack.
The reason is that they all either implemented threaded comments or didn’t put a message limit. The result is that you don’t have to check the conversation all the time, because you can always take part in it later. Even years later. There’s no social isolation effect, no addiction effect and no reason to keep checking.