As long as I invest in a well-known cryptocurrency, I never panic. Because I am more of a HODLer rather than a short-term investor. But if I invest in a new and very risky altcoin, most probably I'll panic when I see a big drop in the price. 
Yeah but that strategy only effective on some Top Altcoins like Ethereum, TRX or even Bitcoin but for some new Coin Or Token we should need to be more careful when there is some huge price movement, It can be good but also can be a bad sign and basically most of them was a bad sign, Rug Pull, Scam Team, Hacked, etc. Well, always DYOR!