I will buy more on every -20-30 percent discounts. I think If you HODLer it makes sense. It has potential and money inside cryptocurrency market isn't huge compared to other financial markets.
I prefer to buy when prices are constant like in the last 2-3 days. When the price fluctuation is high, I don't like it. I find it very risky at those fluctuation times. That's my reasoning for buying at calm prices.