I follow, yet I disagree that "first priority" must always be a reproducer. There are a lot of conditions that can be rootcaused clearly from diagnostics; say, Linux kernel code deadlocks can exhibit as two different (in their stacks) repeatedly shown "task stuck for more than ... seconds" messages; the remainder follows from the code (to see the abba-lock-ordering violation). There's a certain fetishisation of reproducers not unlike the fetishisation of build-time testing - to denigrate a bug because "you can't reproduce it" or "if it doesn't show in the tests it needn't be changed". Personally, that mindset irks me. Fortunately, most developers are happy to learn more about their code any which way. And debugging, tracing, monitoring is cool in itself.