If you hold a cryptocurrency that is profitable, I think you can sell it. If you hold a cryptocurrency that is a loss, I think you should hold it for a long time instead of thinking about selling it 
Yeah that is true. Don't lose hope, the altcoin today experiences down but I think before the year ends the bitcoin may rise. Just hold it and don't sell it. It just take time and be patient
Agree, We need to keep on holding until the markets recovers because selling our crypto investment in a very low price can't help us to get enough funds to divert investment to other coins.