Forex trading can make you huge profit or make you broke in just a matter of minutes because most forex brokers uses up to 1000th of a decimal for their spread thus making the price very volatile causing each trader to gain or loss with just a fraction of price fluctuation in such a short period of time and this kind of actions are very consistent everyday, anytime across all forex pairs compare to BTC trading which most of the day is relatively quiet unless a sudden pump and dump activity occurs or a huge market moving news like the upcoming Winklevoss ETF decision.
FOREX don't have 1000 decimal. they only use 4 and 2 for the Japanese Yen. One reason that can make you loss on Forex is through the leverage they allow for traders who have tons of money on their account. In crypto there is sure what to win, invest on BTC. Investing on BTC won't be losing money with it but then its going to take time unlike on forex that a trader can simple raise their leverage to also amplify the profit for every inflation.