I often lose my temper when altcoins drop sharply.
And in general, I sell altscoin at the bottom
I feel the same way too. Its when your ready to make a trading and wanted to sell your coin because you really needed to trade but suddenly you saw those red lines on the market, it was totally sucks. But due to a reason you really needed to trade because of emergency reasons there's nothing you can do but to make a deal with those red lines. But if there's no such valid reason to trade during those red lines I swear I wouldn't take the risk.