Every company I worked at in the past 10 years has created an internal version of Slack. Four companies.
I think a more likely scenario here is that something good and free escapes containment at some point and Slack’s core product just kind of deflates. Not something better than Slack, but something good enough that people don’t care about Slack any more.
I don’t see it as a question of whether you build it or buy it, but a question of the time horizon for selling messaging software as a business strategy. Most business strategies have a finite time horizon. How long can you continue to sell messaging software before there are too many competing solutions available and you stop making money from it?
Web browsers used to be exclusively paid software, if you were serious. So did operating systems, SQL databases, C++ compilers, and video codecs.
You're too heavily discounting the effort to maintain, deploy, and scale a service like Slack.
I don’t think “categorically different” has legs. I work on the operations & hosting side of applications like this. There’s an operations burden to maintain, deploy, and scale web servers. There’s a burden to rolling out new Linux kernel versions to servers. But we still do it! There would be a burden to running your own Slack, just like there is a burden to running your own email, and people will choose to pay for hosted versions or host it themselves.
And then there are companies and organizations who have strong incentives to self-host to make compliance easier.
Of course it sucked and no one used it except executives and VPs. Everyone else did just enough to meet the minimum quarterly engagement metrics right before performance reviews.
1. They did, and still sell it. You can buy it.
2. They did, and then exited the market. Employees gradually migrated off the internal platform.
3. They weren’t in the business of selling software, and didn’t sell their internal messaging platform (which is idiosyncratic and closely integrated with other internal system).