I often lose my temper when altcoins drop sharply.
And in general, I sell altscoin at the bottom
It is time to buy those coins out ther plenty of them especially those coins that are successful like bitcoins and ethereum. Because if we buy in a lower price we can sell it in much higher price if the value comes back to green. And if you fo not have the money to buy coins, probably you qill just calmly hold your coins whatever it is because you do not wanted to lose money. Just fo not panic when you see that the market are all in red because it always happen and nothins new with it you will get used to it when you are gonna be long in this.
This is a common practice. People at the time of low prices get fearful about the future of the altcoins and they deice it to be sold at the lowest possible price available. This is something that must not be practiced as the price is a subject to change always and so it is possible that it would increase after a downfall and the things would get settled down again in a desirable manner.