I also learn from failure. When the profit reaches 20%, I will withdraw the profit. If I lose 20%, I'll sell. Sometimes it's hard to do. When I sold, I would complain that I could have made more. This is wrong.
This is good that you are learning from your failure because we all need to be some better after mistakes and failures, but you need to rethink about your strategy because if you want to have some good in this crypto market or in trading then surely try to change strategy time by time and work with patients because it's very important in this field without this you can lose your all funds.
First you need to decide what your goal for this because without this you are not able to do any good thing and selling after 20% lose is also very bad because with this attitude you will be completely bankrupt just check all analysis and then put your funds for some long time which will help you to have some good profit.