The mother of all crypto scams is bitconnect. I can't believe that piece of garbage was once a top 10 coin. A lot of suckers fell for the hype and got blinded by greed.
I remember this years ago that one of my friend ask all of us to join bitconnect including me, after several week he just stopped talking about it eventhough I keep asking for it. That's how I know cryptocurrency for the first time, by losing some amount of money first. That's a bit ashamed that I got scammed as my first experience in crypto, but that's also such a blessing that I knew about crypto because of that.