This is great advice.
I found myself sometimes thinking "I don't need to know 'x' to do my job properly", when actually 'x' turned out to be an important thing to know.
After taking in this advice, when I get the same thought again, I hesitate before telling myself I don't need to know it. Maybe I do need to know it!
There are, of course, many things we don't need to know, and no one could never have enough time to learn them all. So I guess the onus is on each one of us to use our best judgement and carefully prioritise learning, so that we can focus on learning the most valuable, useful things.
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