This meme captures the very much the premise of any good incident investigation.
No matter how much one think they’ve got the answer or likely cause of an incident, by going into it in that mindset, they’ve failed before they’ve started.
It is the single most common barrier I see with an organisations own investigations. They may sometimes be in the ballpark, but it’s very rare they’ll be seeing much more than the basics or immediate causes. They’re missing valuable learnings and almost definitely destined to repeat incidents caused by many similar factors if they don’t approach it with an open, yet curious mind.
It’s costly and just bad business to jump to a conclusion too promptly or before gathering the spectrum of data.
So our advice is to make a conscious effort to don’t close your mind with an existing likely cause of an incident investigation. Do the data collection and then rule out what’s not a factor and you’ll often be surprised that there are many more significant factors than one where an individual has screwed up or a single factor has failed. Once you’ve gotten these elements of data together, then put them on a single page and rank them in a hierarchy of most to least significant or systemic. You may actually be surprised that you weren’t as accurate with your initial reasoning as you thought.