Many of us make mistakes, yet sometimes we cannot identify that we still might be in a bad kind of mindset, so we keep making the same mistakes over and over, and staying involved in shitcoins or can's stop trying to trade bitcoin, which can be some of those kinds of mistakes that are hard to get away from continuing to make.
Not going to generalize this but I have noticed that most of the times when you see someone who actually is buying various shitcoins (something I can never call investment) and they probably have been losing money more and they still stick around this same strategy of buying they are people not making mistakes in my opinion but rather people who are actually trying to get rich quick by buying the next pump coin. Sometimes it is hard to actually hard to get this mindset off from them.
It's good to reiterate that greed is the most desastrous attitude an individual will have especially when you're engaging in crypto investments and trading, else one will not stop making the mistakes you mentioned above. I've practically engaged in buying and selling of Shitcoins with the hope of making quick money but in the end it all went south with me because my money went into the thin hair within minutes. I've seen how coins like B3 Shitcoin recently seeing how it rose by hundreds and thousands of leverage but in the end, it crumble and some even disappear completely. The best form of trading and investment in gambling is knowledge, patience and unbiased calculations of profits.