For instance, you might have a day trading strategy that exploits differentials in tightly correlated cryptocurrencies: BTC and ETH, for example. If you think that BTC and ETH are tightly correlated and you see that ETH is disproportionately low, you might buy ETH with the expectation that ETH will rise up again to restore its typical relationship with BTC. However, this might be a case of contagion: the whole market is going down. In this case, your technical analysis could be your downfall: you’ve just bought into a position that’s still going down.
No, the successful trader is not me. I’ve gotten lucky a few times and I’m still refining and trying out strategies; on the other hand, I’m part of communities of people who trade on a daily basis to grow their portfolios, and while some of the results can be attributed to luck, a majority of it is based on fundamentals, good habits, and experience.