When bitcoin drops to $30000, this is a disaster for most traders who buy bitcoin and altcoins at a price high. We didn't expect bitcoin to fall this low, so causing altcoins prices to be dumped very deeply. For traders who have already lost over 25% in trading, then it is best not to cut losses because it will make lose some capital. So believe me, the bitcoin price will back up again and altcoins price will rise again.
being trader does not mean you will continue to Buy and sell because there must be a change of Strategy coz i do this some time specially in moment like this.
remember that when we are buying we must be ready in holding because the price wont always come towards our target but not unless we are willing to sell at losses then we can keep the coins instead.