Re: Worst software ever...
There is, it's called Bugzilla
Not really comparable and, depending on who you ask, equally awful: I personally hate it but YMMV. JIRA is very ambitious attempting to support the whole agile approach which means configuration and training. It's certainly too much if all you want is a bug tracker and, in common with lots of project management software, fails to take into consideration how fallible the meatware is.