I was responsible for getting several development teams on Slack. You see, nowadays few people outside of us hardcore geeks will want to use IRC (my first opti

I was responsible for getting several development teams on Slack. You see, nowadays few people outside of us hardcore geeks will want to use IRC (my first option). And there are things that "modern" chat clients do better. For instance, our monitoring system can post messages to slack with links to images to allow us to display graphs inline, links to runbooks, and even buttons to take actions. IRC won't do that. Second option was Matrix with its (rather cool) open protocol, but the immaturity of clients and lack of integrations was a problem. Almost everything supports Slack, but good luck finding Matrix support. For our own systems this is manageable, but not all are under our control. Also, we would have to host and manage the infrastructure ourselves. XMPP would be great on the integration front (surprisingly, Slack still wins), but once again it's something we would have to manage. There were other options. Rocket.Chat, Hipchat, Mattermost, you name it. Each one with their own drawbacks. So when asked by my manager what should we use, I could just answer "use slack" immediately, no ifs or buts, and most people would be happy with it.Assuming you have nothing against the company, the biggest technical con is the memory hungry client. The other issues are way harder to justify – big companies rarely care about proprietary protocols as long as they have a vendor to yell at.