My costly lesson was 174233 dogecoin. Yes, I had 174233 Dogecoins in my wallet in early 2018, though this amount of coins had little value at the time. But that was my beggining time into cryptocurrency, and I had fallen victim to gambling. I didn't know much more about youtube channels and I didn't know much more about crypto. I just thought about the value of the dollar. Watching some YouTube videos means some gambling videos have started to play with Dogecoin. I started with 100k dogecoin. Then, after some wins, my dogecoin amount becomes 174233. And when things happen, greed takes over. And because of greed, I lost all of my dogecoin in one day. What I made in 20–25 days Though, at the time, I didn't feel particularly sad because money didn't have a high value. But after Dogecoin reached $0.7 each in 2021, I realised how much money I had lost in my life. Though, after losing all of my doge in 2018, I completely stopped gambling, which may be safer for my larger sums of money. if I had all of my doge today, I would be a multi-millionaire today in our village and as a student in our native currency. I think this is the most costly mistake in my life.