Trading Strategies are not constant , it changes with time. If we think the particular method we were taught in the early stages during trading will still work for the market over time, we may keep on losing because the market changes with time. One particular strategy of trading can't be use all the time.
In Cryptocurrency generally profit is taken from buy and sell. Here anyone can research as much as they want, create new strategies and apply them to make or lose money by buying and selling. Now the question is, will everyone follow the same strategy? No. Here different investors can make profit by adopting different strategies. The strategy is constantly changing.