And you think that is enough to keep you winning or profiting for long time and regularly? You must expand your reading to other areas of trading, which includes how the price actions reacts, risk Management, and more importantly study the coin you are to trade it's very essential if not for btcusdt then any altcoin should be carefully monitored before entering trade otherwise you could be rugged pool.
Books might only give us an insight but the experience can still change when we are on the real scene already, especially for something that is unstable like the crypto market. By being aware of it, it can automatically tell us that a stable profit seems kinda hard to achieve. A regular profit is still possible though, same goes with winning in the long term but that is if we already grasp things. He said he read 'some' books, so that can mean that he already explored other areas but it may not be enough yet or he still miss the other, so he will need to keep on moving.
otherwise you could be rugged pool
It is rug pull, not pool. And the ones that are affected the most here are the investors because traders can just trade the foreign/new alts quickly and replace it with the other once they are done.