We troubleshoot when we try to figure out what has gone wrong, or what might go wrong, after we recognise the actuality or possibility of problems. Of course we don’t always know something is going wrong until a failure occurs, and so sometimes troubleshooting only takes place after a failure.
For example, the car has been running rough, but it’s getting along in years and mileage, so this is no surprise. Of course, if the head gasket blows, then in hindsight the rough-running will have been evidence of an imminent failure.
Investigations in general, troubleshooting in particular, often benefit significantly from hindsight. The ability to recognise an impending failure depends significantly on our having noticed patterns through experiences in the world. Patterns and experience cannot be separated.
Identifying failure is its own skill. We might ask: how do we know when something has gone wrong? This, of course, is intimately tied to our sense of expectation, which, in critical thinking, depends on our ability to express what counts as ordinary circumstances.
Part of our task here is to develop a sensitivity to the sorts of things worth making explicit in investigations and recommendations. As always, this will depend heavily on competent exercise of our judgement.