It's a bit controversial but there's a lot of evidence that actively managed funds underperform passive ones. "A Random Walk Down Wall Street"[0] is a good read on the topic.
[0] https://en.wikipedia.org/wiki/A_Random_Walk_Down_Wall_Street
[0] https://en.wikipedia.org/wiki/A_Random_Walk_Down_Wall_Street
When allocating capital to funds you are being adversely selected against: those who can generate returns probably aren't interested in your money (there's a lot more money in the world than profitable trading/investment opportunities).
As such, I normally recommend to people that unless they are professionals and know that they are doing or HNW (say >50mil), they stick to ETFs for the bulk of their portfolio. To be clear this isn't the optimal strategy, but it's easy and it mostly works.
Is there any proof of that? Some traders of course will get very rich, just like some lottery-players.
https://www.gerd-kommer-invest.de/der-beste-fonds-aller-zeit...
If we're talking about short-term traders, yes. There's firms and traders that make money almost every day of the year.
If we're talking about investors with 4 week+ holding periods, then I agree the evidence is much more flimsy and the luck explanation (or risk premium explanation) can apply very often (or all the time).
In investing, the first thing you have an influence on is avoiding fees (go passive).
The second thing you have an influence on is time (remain invested).
For me, I decided to follow Steve Clark's advice of "Do More of What Works and Less of What Doesn't". I invested in a bunch of different things including ETFs, managed funds, futures, individual stock picks, IPOs, etc. and I found managed funds that seemed to work better than ETFs (though 5 years is not really enough time to know for sure), so I pumped more into the managed funds that were working.
Investing only in IPOs seems to work well as well but the hardest part for me was knowing when to sell (which in my case I almost never sell and I often miss the best opportunity to cash out my IPO investments).
I am sure there are some bad managed funds, probably more bad ones than good ones. I'm certainly not saying managed funds are a better choice overall than just going "all-in" on Vanguard, but picking out a few managed funds to try out after doing a couple of hours research is also not a strategy that should be completely written off either, at least in my experience.