The difficulty describing itself is core to Slack’s challenges to date, and the idea that once companies start using Slack, they can’t live without it is core to its promise.
So much productivity is fueled by negative emotions. You're afraid of getting a bad grade as a teen, so you study for tomorrow's big test late into the night, mostly out of fear and with the knowledge that you'll be exhausted tomorrow. There's no joy in it, just a fear of not being good enough, of disappointing someone, of ruining your future.