What if they decide to keep trading and losing money until they master a strategy that will benefit them in trading
If they decide something like that then still they won't be able to make profits as a trader because losing enough money will change their beliefs regarding trading and they'll somehow get a feeling that the market is always manipulative. I know some of them may become good traders but most of them will give up on trading.
A newbie in trading will certainly give up when he sees that he is losing always because it is money that we are talking about here. Instead of losing all that money to trading, if you just start investing it will save your capital and also give you profit in the long-term.
Mastering trading is not easy and coming up with your own strategy that will favor you in the market takes much time because trading is complex and this is why majority of people who tries trading always run at loss often.