When you learn about price action, you'll know that 99.9% of the time these drops are fake.
They are done by the market makers to shake weak hands, those whose hearts speed when they see big red candles, the premature sellers.
The market makers do it because they want to buy their bags, their assets for cheaper prices.. Why pay 3.8$ for 1 FXS when you can pay 3.6$..
So they sell some of their bag and this is enough to cause panic and fear in the weak and make them sell and accept little profit.
Of course, everything is done by bots, they just set the Parameters and leave them do all the work.