One pretty simple lesson: Save some of your money even if it's from passive income. Nothing lasts forever.
BTW: What's up with the "only make something meaningful" propaganda lately? Nothing wrong with profits, just keep in mind that you can't outsmart the whole world forever: like arbitrage in an efficient marketplace, your low hanging fruit are eventually picked by everyone.
Of course there is something wrong with it. It is a zero-sum activity (or negative-sum, since it takes work) that moves value around instead of creating it.
BTW: What's up with the "only make something meaningful" propaganda lately? Nothing wrong with profits, just keep in mind that you can't outsmart the whole world forever: like arbitrage in an efficient marketplace, your low hanging fruit are eventually picked by everyone.