I guess one way to explain it is that Hipchat feels like an enterprise product, and Slack feels like a consumer product. The difference being that enterprise products get used because some high-level person says, "Lo, all my vassals shall now use Hipchat." Which means that user experience is secondary. Whereas consumer software has to earn each user, meaning that it works harder to please and support those users.
JIRA's BDUF approach to ticketing/bug tracking pleases middle managers whose job is to spend all day clicking around arcane interfaces and finding a way to generate a report that shows their team is highly productive, but it's painful for actual doers to get in there and move stuff around, which means it rarely gets done, which means that the tracking is not very reliable, which means that the value of the bug tracker is dubious. The most important feature any bug tracker can have is that it's low-friction enough that most people will actually use it.
JIRA has tried various things to make this less onerous, including GreenHopper/swimlanes, an attempt to remake JIRA into a Trello-like drag-and-drop interface, but it just never seems to click the same way. For example, today, when I tried to move a ticket in JIRA from the "New" swimlane to the "Done" swimlane, I got a "WORKFLOW EXCEPTION".
Product managers need to learn a simple lesson: if a user wants to use power user features then you should let them because there's a good chance they know what they are doing.
