1. Not digging deeper the first time I heard of, right around when Snowden did his thing in 2013. No one told me about it, it was something I read in passing and it was more in the context of anonymous money which I just assumed was for buying drugs on the darknet.
  2. Not understanding the difference between bitcoin and shitcoin. Fortunately I met a maximalist fairly early in my journey so I didn't lose much.