Market is very unpredictable, you will just lose money if you sold your crypto at a low price because you think it will dump more in the next coming days.
Yes you are right because Bitcoin is dumping many are selling at low prices. They may think that bitcoin will be more dumping in front of it so they are now selling at a low price. They may not know that Bitcoin had been dumping in 2018 and it's okay again. Now maybe Bitcoin has been dumping and it's okay in the future if they sell it, they can get a good profit.
I hate people selling at low prices because they are eventually contributing to the bear market by selling. Then I also feed bad for some because not everyone has a humongous capital and they cannot risk the market crashing even further. Not everyone has a backup plan or secondary job so they have to cut their losses as much as they can.
If you ask anyone who sold their coins for cheap, to honestly answer this: "Do you really feel BTC will never go up again?" they will almost all answer they believe it will go up, but because it might be their life savings, they cannot just risk it either. Some people are doing leverage and futures trading and hence they automatically lose when a big crash takes place.