In the world of trading and investing is pretty hard not to loose money. Specially because investments involve risk. So I think those rules are pretty pretty hard to do.

The issue of diversifications is that is hard to know how all markets work. So is hard to be a crypto expert but also a stock expert and a derivate market expert. Althought you might go under the same rules, the amount of knowledge you need to have is pretty hard.

Of course you can get out of financials and invest into more ethereal ways of investment like a business, real state or invest in your brain.