I've know a number of people who were
really good at one thing or a handful of interrelated things. That might be a programming language or specific technology, some business domain or something else, but I've never quite figured out how they did it.
I've tried the deep dive thing a few times and always come out frustrated. It seems like the important stuff that differentiates the expert from someone with casual knowledge isn't documented. Sometimes it's explained by the knowledge being locked behind a paywall or IP protection of some sort. Sometimes its not, but the knowledge seems to be locked in the brains of a few individuals or organizations and can only be unlocked if your'e lucky enough for them to take you in (employment at a company that specializes in something, or having a mentor type relationship with another expert). On the other hand, a minority of the experts I know are nearly completely self taught and I'm struggling to figure out how to manage. Generally as a hobbysit Like I said every time I've tried to deep dive I reach a point where I'm not sure what I'm missing, where to find it.
Anyone who tries to convince you that your should pay for advice on "how to become an expert" has expertise at only one thing: lying.
PS: I can teach you how to be an expert at spotting liars. For 5 dollars I'll tell you the secret.
Behind paywall 1: First lesson - don't pay for lessons on expertise. For 5 more dollars, I'll let you read chapter 2
Behind paywall 2: You are almost there! So close! You should be getting familiar with the trick by now. There was a secret lesson in part one. I'll tell the secret behind the trick for just 5 more dollars.
Behind paywall 3: Fool me once, shame on you. Fool me twice, shame on me. Fool me three times, and now we are here! Wanna know how I fooled you three times? Only 5 more dollars!
Now you are 15 dollars into spending 5 dollars on how to spot a liar. Just 5 more dollars!
Once you figure out the trick, you can consider yourself an expert.