> Quit thinking and look (get data first, don't just do complicated repairs based on guessing)
From my experience, this is the single most important part of the process.
Once you keep in mind that nothing paranormal ever happens in systems and everything has an explanation, it is your job to find the reason for things, not guess them.
I tell my team: just put your brain aside and start following the flow of events checking the data and eventually you will find where things mismatch.
There's a book I love and always talk about called "Stop Guessing: The 9 Behaviors of Great Problem Solvers" by Nat Greene. It's coincidental, I guess, that they both have 9 steps. Some of the steps are similar so I think the two books would be complementary, so I'm going to check out "Debugging" as well.
I worked at a place once where the process was "Quit thinking, and have a meeting where everyone speculates about what it might be." "Everyone" included all the nontechnical staff to whom the computer might as well be magic, and all the engineers who were sitting there guessing and as a consequence not at a keyboard looking.
From my experience, this is the single most important part of the process. Once you keep in mind that nothing paranormal ever happens in systems and everything has an explanation, it is your job to find the reason for things, not guess them.
I tell my team: just put your brain aside and start following the flow of events checking the data and eventually you will find where things mismatch.