If you have a few minutes to spare, I highly recommend this post: LEGO’s letter to parents, and how not to tell a fake when you don’t see one
It’s honestly one of the most approachable deep-dive reports I’ve seen. As a software engineer, when I find issues in systems I maintain, it’s my job to debug them. It’s mostly a matter of checking the most common sources of problems: memory usage, disk space issues, concurrency issues, a minor bug in the code.
Once in a while, the root cause is more devious. That’s when it becomes appropriate to do a deep dive.
Thoroughly diagnosing and solving a problem is a long process. Sometimes, it takes multiple days. It’s difficult to convey what it’s like to go down a rabbit hole like that.
This blog post about a pamphlet from LEGO is a very approachable version of such a deep dive.