IMO, you are referring to short term/intra day trading,
Trading is good if you understand it, but some people will never understand how to trade but they will continue to lose.
There is nothing to understand for intra day/short term traders. You will simply lose in the long term just like a casino because you are essentially betting on random noise (I hope you are trading in big enough efficient markets) . I am talking about an average trader who will always fall short in front of insiders and ultra fast 'High Frequency Trading Firms'.
it is a good advise for you to just hold for bull market to come.
It is a long term trading not 'investment'. There is a difference in approach and mindset when it comes to investment, the time frame will also be much bigger than just waiting for bull market.