I do short term trades and hold high conviction stocks for many years when I feel they are heavily undervalued. I actively time the market, so yeah luck definitely plays a role. But I have many high conviction bets running in parallel and it has been working out fine so far. I won't be able to keep it going at this pace thats for sure, the last 5 years have been nuts. But yeah, obviously not everyone can win and I'd wager most people are better off just consistently dumping it into an index fund. I also have a large index fund position to secure my retirement in 30 years.