There are two aspects to investing: return and risk.

After a long bull market investors tend to forget about risk & focus only on return. This one a key reason why value investing tends to go out of favour, because value investing places a lot of emphasis on risk reduction.

An emphasis on a margin of safety, scrupulously avoiding overpayment, and being humble/realistic about the degree to which you can foresee the future, seems unduly conservative during boom times.

However, when the shit eventually hits the fan, which given enough time it always does, certain stocks & investors loaded up in them can see losses of 50-90%, and investors are reminded about the importance of risk. Value investing tends to then come back in vogue.

Overconfidence is something that plagues most investors. It's a problem because it causes you to underestimate risk. At least 50% of your time should be spent thinking about the downside and all the ways you could lose money, instead of simply focusing on the upside.

The stocks I tend to buy are not the stocks where I think I can make the most money. The stocks I tend to buy are the ones where I find it hard to envisage a realistic scenario where I would lose money/overpay.

During good times, this will mean you pass up a lot of profits in bubbly sectors. But it also means you grind out steady profits without taking much risk, and you sidestep major blowups, which happen from time to time, and always live to fight another day.

I have about 180 stocks in my portfolio, and I cannot remember the last time a single one dropped 10-20%+ on a profit warning or earnings announcement.

That's not genius, it's discipline. It's being able to say no/I don't know often, and only investing in very specific situations where expectations are low and your downside very limited. If a stock drops 20% in a day you probably own something expensive w elevated expectations.