Currently I own a lot of altcoin, I bought them at ico. My account is being downgraded several times. There are many people who say bitcoin will continue to decrease, so altcoin prices also decreased compared to USDT. So now, should I sell them and wait for the price to buy back? Give me advice 
In addition to the market movement, the prospects of projects for which tokens were issued are very important. Therefore, some tokens should be sold in any case, while others should be kept regardless of the rise or fall of the market. In cryptocurrency is quite difficult to predict the price. Therefore, we will lose in any case, but in general it brings us a good profit.