Elon Musk says

“Never chase the next hot thing. Stop trying to chase the wave. You will never catch it. You always for the most part find out about that stuff too late. Instead, do what you are really passionate about, what you really love. That will position you before the wave even hits, and you will find out about whatever it is before the wave starts, before it gets hot, and that is how you take advantage.”

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“Measuring programming progress by lines of code is like measuring aircraft building progress by weight.”

“If you give people tools, and they use their natural abilities and their curiosity, they will develop things in ways that will surprise you very much beyond what you might have expected.”