[sgerenser]

The worst part is, even the ones that DO benchmark against the S&P500 or similar are almost always doing it wrong. I have a friend who owns TSLA stock. Of course it has done much better than the S&P over the past several years, so he thinks "it's easy to beat the market, especially if you know a lot about tech." But he's comparing just that ONE investment, not his entire portfolio of other (many failed) investments, weighted by dollars. I know he put a bunch of money on a couple of altcoins and probably several other losing stock picks, but he never talks about any of those other investments.

[arbitrary_name]

More importantly (and what you're kind of alluding to) is the RISK - sure, Tesla is beating the SP500 - but how about a week from now, or a year? He is taking on significantly more risk compared to someone who just holds the SP500 - that's fine if it matches your risk appetite, but most people fail to consider the other side of the risk/return coin.

Likewise, a good understanding of the overall portfolio is key - and not just investments. For example, if you work at Tesla and hold mostly Tesla shares you are running an even higher risk than the average Tesla investor - the risk of you getting laid off is closely tied to Tesla shares tanking - and failing to diversify away that risk can hit many of us very, very hard.