Practically, you are right because today's market has an answer to this. There are many surge and the most are from the altcoins that we never believed to be called coins. Trading has made me to adopt a method that has potential to handle risk, I mean potential risk. Whenever I trade with altcoins, I usually pick my profit at 2-4%. This is how I possibly minimize my risk.
Speaking as such I made some resolutions that help me in trading. For example, I promise myself to never trade an altcoin that has been in the market for less than 2 months. I know I miss a lot of big earning opportunities but at the same time I don't make big loss either as I used to earlier, there are lot of pump groups in telegram that actually made me feel like this coin is going to be pumped very soon but thankfully with time I learned that "no one will ever serve you food on plate" you have it do it yourself and anyone who says they will pump a coin are doing nothing but getting their coins sold by creating such hype.
So, my simple method to minimize risk - Just don't trade new pairs and don't expect too much profits from the heavy pairs like ETH/BTC won't fluctuate too much so just keep making smaller but regular profits.