Many newbie and crypto enthusiastic think trading is easy until they lose on the first day, 1 week,1month, 1year and they finally quit.
A year is long for a any serious trader to adjust to any mistake. I don't think there is a trader that will quit after waiting and patiently trying for 360 days only for them to quit. Unless such trader don't have a vision, it's very easy to learn trade and map out mistakes for such period of time. In addition, trading is easy when explained too but when you do it yourself, you will feel the hard part but that is the best for any person that want to learn trading fast.
There are common mistakes they usually makes which are,
Remember trading requires not just strategy, but discipline
To summarize everything you wrote, trading mistakes can be adjusted by risk management. If you put risk management before everything on your trade, your mistakes will be less, the remaining mistakes that I can point out depends on how you understand trading. A serious trader will do a proper research, a trader who want to make profit will learn how to control his emotions, a real trader will make plan which is still risk management.