I regret that I did not know about the crypto currency several years ago that I sold the ETH for $ 10 that I did not delve into the trade when it just developed, which did not recharge at take-off to $ 20,000 and drop to $ 4000 .... 
I learned about crypto currency in time, but I could not immediately understand the potential of this concept. Initially, I thought it was a pyramid. Therefore, in fact, all the most profitable times passed by me. I really regret this.