1. Do not remember electronic wallet password
2. Do not back up your wallet
3. Do not research new services
4. Buy and sell based on feelings
5. Leave your money in the electronic money floor
6. Waste time on faucets (we all did)
7. Collect dust and pay high fees on it
8. Leave coins in an exchange
9. Trust the wrong people and get scammed
10. Panic at a price correction
I agree with this answer, this will happen if you don't have enough knowledge in bitcoin and in crypto world but if you can adopt and know what bitcoin is all about you will be one of those successful earners.