When I started investing, I was naïve and bought into concept of highly concentrated bet, value investing, double downing, buying more of cheap stocks. I chased one stock to bankruptcy and lost 40% of my portfolio.

Lesson learnt. No more concentrated bets. Just spend more time you can definitely find 50-60 excellent companies, high growth disruptors, you can put equal amount of money on those stocks. Follow them every yearly or two yearly; Don't listen to quarterly earning calls;

Most of the time; EC is distraction, if EC was really bad, the price action of stock will tell you that and you can always have time to reverse your course. Since you have not invested lot of capital on it first place, you don't have to take decision quickly

IMO, like we don't prefer company who has customer concentration, concentrated portfolios also have similar risk to individual investors. Ask to people who invested in luckin coffee, wirecard, GE, BA, Valeant...

Now Valeant reminds of Sequoia fund; I had heard that they had dedicated analyst tracking Valeant for them (so much of due diligence) and was 36% of their portfolio at one time; I don't need to tell anything more. Its all over the internet.

When an investor has concentrated portfolio, it stocks go down, you are anxious that if you have wrong choices and if it goes up you always have impetus to trim it; coz you always think; "Oho stocks will not go up for ever"; just forces you to make more decisions and hence likely

making more mistakes and lead to timing issues...